Cant transfer files over FTP on Android 15

So I just got my Retroid Pocket G2 which comes with Android15 and it seems it behaves different from older chips and Android versions like RP5 and RPC.

I was not able to get FTP access throgh Primitive FTP or Amaze File Manager from my Steam Deck using Dolphin manager on the same network. It either did not connect or reported not having write access to the folder (android had all files permission enabled).

Is there any way to get access to my RPG2 over my network from my Steam Deck or other Android devices?

Thanks.