Slow upload/download even after fresh install

I had nextcloud for more then 6 month no problem. got my 50mb/s uploads (That’s my network plan).
For the last 2 month I got less then 2mb/s inside/ouside network. I saw that I might need to disable http2 (wich is not enable). I had to change from centos to debian so I took the chance te reinstall nextcloud, same issue. That’s wierd because I tried to install it on a VM with the same setting and got 37mb/s.

Btw sorry forr my english and that the topic seems to be a duplicate