App constantly asks for username and password


I have installed nextcloud on my Intel Nuc using Ubuntu+LAMP

I’m currently using it via external IP address, this is for testing purposes and I will be setting up a something via no-ip at a later date along with a free SSL.

When I try to connect via my external IP address via the Android App, i’m constantly forced into a login state - I type my password and then it looks to be loading but sends me back to a login screen.

Can anyone help?