Driver's side Running lamp

Replaced bulb, fuse... still not working. Any insight?
Apologies in advance if this is a redundant question, at least I'm in the correct section!!

 

I'd check the bulb socket itself. Over time these sockets may get moisture in there and small rust builds up. Maybe see if the bulb is firmly seated in the socket and all the socket prongs are not collapsed or not contacting the base of the bulb. Other than that, maybe wiring harness has small short, or ground wire needs to be re-grounded (cleaned).