Auto-Fill not working ...even after multiple attempt and reached out to CRA

Hi ,

I have issues connecting to CRA my account for fetching my data. It result into attached error. I reached out to CRA tech support and they claim nothing wrong on their side, and asked to reach out to TT instead. Not sure how to resolve this. I have been stuck on my return since 1 month ...I tried uninstall/install software, rebooting machine multiple times, changed defualt browser to authenticate etc...but no luck....still getting same.

Please help as soon as possible, or guide me.