How do I get rid of version 10 Postgresql completely ?

Hello,

Whenever I start pgAdmin4 I will get this invalid literal for int() with base 10: 'None'.

And the other time I get this see version 10 still exist while playing with Ubuntu WSL.

I had uninstalled version 10 so I am not sure why there is still 
remnant lying around in my Windows 10 system.

Can someone kindly advise me how to get rid of PostgreSQL 10 completely.

Thanks in advance,
Karen