I have the MacBook Pro (13-inch, 2020, Two Thunderbolt 3 ports) and I've been having weird charging issues (I recently upgraded to macOS Big Sur if thats relevant). When I connect the charger it won't always charge, and when I press the battery symbol it only says "not charging". One of the ports never works, but the other works after its been plugged in for a little while. The battery still drains when the charger is connected but not charging.
I've tried resetting SMC, troubleshooting/diagnostic scan shows nothing wrong, the ports and the charger looks undamaged...
The battery works completely fine as far as I know other than this, this is a recent issue.