Hello,
Hard to say what’s going on with your instance. Sometimes I run into this issue when rebuilding VIVO on top of an existing webapp. Restarting Tomcat fixes the issue for me in this case. Do you see any errors in vivo.all.log or catalina.out? I suspect this is more of a Tomcat issue than a VIVO issue, but that's just a guess.
As an aside, the current version of VIVO is v1.12.2. It includes a lot of updates, fixes, and features you won't see in v1.9, which is almost 6 years old at this point. If you can, I encourage you to use the current version.
Benjamin