HI,ALL
I met an issue when I attempted to add reviewers or CC on UI.it showed "Error 500 (Server Error): Internal server error Endpoint: /changes/*~*/suggest_reviewers " ..
did anyone know how to solve this issue ?

[2020-02-05 10:05:18,107] [HTTP-176] ERROR com.google.gerrit.httpd.restapi.RestApiServlet : Error in GET /changes/python1~41/suggest_reviewers?n=6&reviewer-state=REVIEWER&q=1 [CONTEXT project="python1" ]
com.google.common.util.concurrent.UncheckedExecutionException: java.nio.file.InvalidPathException: Illegal char <:> at index 47: E:\gerrit\git\All-Users.git\refs\groups\us\user:test
at com.github.benmanes.caffeine.guava.CaffeinatedGuavaLoadingCache.get(CaffeinatedGuavaLoadingCache.java:65)
at com.google.gerrit.server.account.GroupCacheImpl.get(GroupCacheImpl.java:112)
at com.google.gerrit.server.account.GroupMembers.listAccounts(GroupMembers.java:95)
at com.google.gerrit.server.account.GroupMembers.listAccounts(GroupMembers.java:84)
at com.google.gerrit.server.restapi.change.ReviewersUtil.suggestGroupAsReviewer(ReviewersUtil.java:416)
at com.google.gerrit.server.restapi.change.ReviewersUtil.suggestAccountGroups(ReviewersUtil.java:364)
at com.google.gerrit.server.restapi.change.ReviewersUtil.suggestReviewers(ReviewersUtil.java:303)
at com.google.gerrit.server.restapi.change.ReviewersUtil.suggestReviewers(ReviewersUtil.java:220)
at com.google.gerrit.server.restapi.change.SuggestChangeReviewers.apply(SuggestChangeReviewers.java:95)
at com.google.gerrit.server.restapi.change.SuggestChangeReviewers.apply(SuggestChangeReviewers.java:40)
at com.google.gerrit.httpd.restapi.RestApiServlet.service(RestApiServlet.java:498)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
at com.google.inject.servlet.ServletDefinition.doServiceImpl(ServletDefinition.java:290)
at com.google.inject.servlet.ServletDefinition.doService(ServletDefinition.java:280)
at com.google.inject.servlet.ServletDefinition.service(ServletDefinition.java:184)
at com.google.inject.servlet.ManagedServletPipeline.service(ManagedServletPipeline.java:89)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:85)
at com.google.gerrit.httpd.raw.StaticModule$PolyGerritFilter.doFilter(StaticModule.java:436)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
at com.google.gerrit.httpd.GetUserFilter.doFilter(GetUserFilter.java:92)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
at com.google.gerrit.httpd.RunAsFilter.doFilter(RunAsFilter.java:120)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
at com.google.gerrit.httpd.AllRequestFilter$FilterProxy$1.doFilter(AllRequestFilter.java:133)
at com.google.gerrit.httpd.AllRequestFilter$FilterProxy.doFilter(AllRequestFilter.java:135)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
at com.google.gerrit.httpd.RequestCleanupFilter.doFilter(RequestCleanupFilter.java:60)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
at com.google.gerrit.httpd.RequestMetricsFilter.doFilter(RequestMetricsFilter.java:57)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
at com.google.gerrit.httpd.RequestContextFilter.doFilter(RequestContextFilter.java:64)
at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
at com.google.inject.servlet.ManagedFilterPipeline.dispatch(ManagedFilterPipeline.java:121)
at com.google.inject.servlet.GuiceFilter.doFilter(GuiceFilter.java:133)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1610)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:540)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1700)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1345)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:203)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:480)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1667)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:201)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1247)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:144)
at org.eclipse.jetty.server.handler.RequestLogHandler.handle(RequestLogHandler.java:56)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
at org.eclipse.jetty.server.Server.handle(Server.java:505)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:370)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:267)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:305)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:117)
at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333)
at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310)
at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168)
at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126)
at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:698)
at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:804)
at java.lang.Thread.run(Unknown Source)
Caused by: java.nio.file.InvalidPathException: Illegal char <:> at index 47: E:\gerrit\git\All-Users.git\refs\groups\us\user:test
at sun.nio.fs.WindowsPathParser.normalize(Unknown Source)
at sun.nio.fs.WindowsPathParser.parse(Unknown Source)
at sun.nio.fs.WindowsPathParser.parse(Unknown Source)
at sun.nio.fs.WindowsPath.parse(Unknown Source)
at sun.nio.fs.WindowsFileSystem.getPath(Unknown Source)
at java.io.File.toPath(Unknown Source)
at org.eclipse.jgit.internal.storage.file.FileSnapshot.<init>(FileSnapshot.java:257)
at org.eclipse.jgit.internal.storage.file.FileSnapshot.<init>(FileSnapshot.java:238)
at org.eclipse.jgit.internal.storage.file.FileSnapshot.save(FileSnapshot.java:135)
at org.eclipse.jgit.internal.storage.file.RefDirectory.scanRef(RefDirectory.java:1153)
at org.eclipse.jgit.internal.storage.file.RefDirectory.readRef(RefDirectory.java:1123)
at org.eclipse.jgit.internal.storage.file.RefDirectory.readAndResolve(RefDirectory.java:326)
at org.eclipse.jgit.internal.storage.file.RefDirectory.exactRef(RefDirectory.java:348)
at com.google.gerrit.server.git.meta.VersionedMetaData.load(VersionedMetaData.java:132)
at com.google.gerrit.server.group.db.GroupConfig.loadForGroup(GroupConfig.java:148)
at com.google.gerrit.server.group.db.Groups.getGroupFromNoteDb(Groups.java:80)
at com.google.gerrit.server.group.db.Groups.getGroup(Groups.java:73)
at com.google.gerrit.server.account.GroupCacheImpl$ByUUIDLoader.load(GroupCacheImpl.java:192)
at com.google.gerrit.server.account.GroupCacheImpl$ByUUIDLoader.load(GroupCacheImpl.java:179)
at com.github.benmanes.caffeine.guava.CaffeinatedGuavaLoadingCache$SingleLoader.load(CaffeinatedGuavaLoadingCache.java:136)
at com.github.benmanes.caffeine.cache.LocalLoadingCache.lambda$newMappingFunction$2(LocalLoadingCache.java:140)
at com.github.benmanes.caffeine.cache.LocalCache.lambda$statsAware$0(LocalCache.java:139)
at com.github.benmanes.caffeine.cache.BoundedLocalCache.lambda$doComputeIfAbsent$14(BoundedLocalCache.java:2379)
at java.util.concurrent.ConcurrentHashMap.compute(Unknown Source)
at com.github.benmanes.caffeine.cache.BoundedLocalCache.doComputeIfAbsent(BoundedLocalCache.java:2377)
at com.github.benmanes.caffeine.cache.BoundedLocalCache.computeIfAbsent(BoundedLocalCache.java:2360)
at com.github.benmanes.caffeine.cache.LocalCache.computeIfAbsent(LocalCache.java:108)
at com.github.benmanes.caffeine.cache.LocalLoadingCache.get(LocalLoadingCache.java:54)
at com.github.benmanes.caffeine.guava.CaffeinatedGuavaLoadingCache.get(CaffeinatedGuavaLoadingCache.java:59)
... 61 more
gerrit version is 3.1.2,db is H2, apache24 ,installed on windows 10.
PLEASE HELP ME
THANKS