Keyboard problem.
When I type something in my keyboard and specially when I type A key it may stuck and stay lagging from itself , it's not a Software issue but it is a hardware issue.
MacBook Pro 13”, macOS 10.15
Question marked as
You do not say what exact Mac this is ...
How to clean the keyboard of your MacBook or MacBook Pro ...
if no resolve
See if you qualify here: https://support.apple.com/keyboard-service-program-for-mac-notebooks