All Of A Sudden Firebase Authentication Not Working! Unexpected Response Code 400

My code was working perfectly fine for the last month didn't even touch it for a while for modifications or edits. But now, this problem came up and ruined my app for good. Please

Solution 1:

In your Log its showing 'want to send authenticated request, but no Google account on device'. Is this crash is coming for every device. I prefer you test this in other devices.