PaperUI MyOpenhab Error 404

Hello together,

I setup Openhab on my RPI3 mith myopenhab. The connection runs fine, but if I want to change s.th. I always get
"ERROR: 404 OK"
I have a slow upload on my DSL-Connection. Maybe this can cause the problem?
If I access PaperUI local or even through VPN than it runs fine and the error does not show up
Any experience with this problem?

THX,
Stefan

What URL are you using when trying to connect through myopenhab?

Does your system show online in myopenhab.org?

Hello I always log into myopenhab and then click on PaperUI.

Everything shows up and works fine until I want to change s. th. I cannot rename a Thing or Item. The Error 404 shows up and the Thing has the same name than before. I cant install e. g. new bindings.