Hi @alexCa,
Without knowing how you set up the proxy, there’s very little we can do to help. Please provide a better, more clearer question. Please see:
-
[HowTo] Provide System Information.
At bare minimum we would need you to please provide a detailed description of the problem faced, as well as the output to:
inxi --admin --verbosity=8 --filter --no-host --width -
[HowTo] Post command output and file content as preformatted text.
Please also note and heed: Forum Rules - Manjaro
Those with privacy concerns: note that when -z, or --filter is used, all personally identifiable information is filtered out from the resulting inxi output. 
This is a vast subject, as evident by:
https://wiki.archlinux.org/title/Proxy_server
So we’d need a lot more information.