Windows 10 Thunderbird Connection Problems

I still use Thunderbird on an old desktop and for the past month or more, I've discovered with some sort of communication error or the direct pop-up that I cannot login to server and it asked me to 'retry'/'Enter New Password"/"Cancel" and it's beyond frustrating. I'm on the verge of just uninstalling this for my emails and use another platform. Before so, since I've been using TBird for a long time, I figured I'd consult some experts here to guide me how to navigate this annoyance. ANY suggestions would be appreciated. Thank you.