SOL init error

[Marc]

Dear List,

We have a system running DSpace CRIS 5.10 with the following

Server version name:   Apache Tomcat/8.5.54 (Debian)
Server version number: 8.5.54.0
OS Name:               Linux
OS Version:            4.9.0-18-amd64
JVM Version:           1.8.0_322-8u322-b06-1~deb9u1-b06

Browsing to the home page gives an Internal System Error.

Looking at the log for /var/log/tomcat8/localhost.2023-02-14.log

Getting the following message 

msg=SolrCore 'search' is not available due to init failure: Error opening new searcher,trace=org.apache.solr.common.SolrException: SolrCore 'search' is not available due to init failure: Error opening new searcher

Digging deeper it seems to be caused by

Caused by: org.apache.lucene.index.CorruptIndexException: codec mismatch: actual codec=CompoundFileWriterData vs expected codec=Lucene41PostingsWriterPos (resource: MMapIndexInput(path="/home/dspace/solr/search/data/index/_o42_Lucene41_0.pos"))

Any suggestions about how I might go about fixing this?

Kind regards
Marc