Sonarr Password

Sonarr version (exact version): 4.0.9.2244
Mono version (if Sonarr is not running on Windows):
OS:
Debug logs:
Description of issue:
I have forgotten the username and password to get into Sonarr, am I just our of luck or is there a way to fix this?

This is covered in the FAQ: Sonarr FAQ | Servarr Wiki