Rider and Continue not allowing auto completion with cpp but h files

[MaxBPMOnGitHub]

This used to work fine, then it worked sometimes, now not at all. Using Rider 2025.2.4. Continue is in the latest version the plugin store of Rider gave me, using it with Ollama.
Since the completion is fine with .h files (and py files) I am pretty sure this is a config question but I fail in finding an answer since weeks now.

I would appreciate any help! I do not need Rider's own AI or any special autocompletion from them, just Continue to Autocomplete again. All settings default would be fine for me. Maybe it is just a single flag? I tried turning off almost all in Rider, set all back to Default, but no difference. This is frustrating, Continue used to work out of the box for me.

Thanks a lot!