Plugin stopped working. How to diagnose?

[Civil-Code]

The plugin has worked for a long time, but after loading some more models (with ollama) and deleting an old one, it stopped working:

"Generating response .... "
=> "Request timed out. This may be due to the server being overloaded."

Ollama chat on CLI (ollama use myModel) and LMStudio both work.

I already tried

• refresh the models in ProxyAI settings
• uninstall + reinstall ProxyAI
• reboot system
• Invalidate caches in IntelliJ.

Which steps can i follow to diagnose the problem?
Uninstalling the plugin didn't clear the user data, because old chats reappeared after installation. How can I do this?