Openhab running behind Reverseproxy

Im running Openhab and Grafana on the same Host behind a Nginx Reverse proxy.

I have my local Lan set to allow - This is working perfect.

I can access openhab from outside the lan when I enter username and password setup for the proxy, but if I access pages on Openhab Basic UI where I share static Grafana charts I’m prompted for username and password (The password for Openhab doesn’t work now).

I believe it must be some kind of permission problem, hope someone can help me solve this?

Best Nanna