Flutter and gsheets read and write V2

I have a flutter app that uses google sign in and reads and writes to gsheets with a gscript. The Google sign in works fine, but when I go back to the starting screen, I can't log back in. The write to gsheets works fine, but when I try to read, I get null response back from gscript.
Can someone please help me fix these issues?
Thanks in advance.