Nextcloud reverse proxy fail

I have nginx running as basically a reverse proxy sitting in front of several apps running in docker, when i try and use nextcloud i’m getting issues being able to upload photos to the server and such

the only real error i can see is on nginx debug logs

2023/04/20 12:22:32 [info] 477#477: *4023 client sent invalid header: “http.protocol.single-cookie-header” while reading client request headers, client: 192.168.0.51, server: cloud.domain.net, host: “cloud.domain.net

there are no errors in the error log on either the nginx reverse proxy or the nginx logs from the nextcloud container

does anyone have any ideas for the cause/fix for this? thanks