[Fixed]-Why do i have 'relation does not exist' when just running 'makemigrations'?

Your TrafficForm is doing something it shouldn’t, which is querying the County objects at import time. While you had an existing database, this was OK(*), but now that you’re starting from scratch it will complain.

You should change that form to use ModelChoiceField.

(*) it’s almost always a bad idea to do this anyway, because new objects won’t be visible in that field until the process is restarted; but in your case I guess new County objects are not often created.