Having alot of various authentication issues

[Alan Fleming]

Initially I was stuck trying to pull a repo, but getting an error message.

Eventually I discovered that I needed to authenticate my bitbucket account under options within sourcetree. After that I was able to pull and push changes with no problem (for that day). Now suddenly today I cannot 'push' changes, getting the same error. I went in to options to authenticate the user, but this time it did not fix the issue.

"git -c diff.mnemonicprefix=false -c core.quotepath=false --no-optional-locks push -v --tags origin alan:alan
remote: You'll need to authenticate with a valid app password. You can create an app password from your account at https://bitbucket.org/account/admin/app-passwords
fatal: unable to access 'https://bitbucket.org/...(project)...': The requested URL returned error: 403"

I tried to create an app password, re-authenticate the user, delete the passwords to force a prompt. Im at wits end here, I thought this was taken care of yesterday.

Is there anyway to set it up, so it knows that sourcetree on this computer is authenticated and avoid this issue in the future?