A different lock problem

Hey guys and gal,
I just brought home my new (to me) ‘01 v6 double cab with power doors and power windows. I am having an issue getting my doors to lock. They lock fine from both switches on the inside and fine from the exterior on the passenger side. However the key will barely move in the lock direction on the exterior drivers side. They unlock as they should from every switch. Any tips?

 

I never lock my doors with the key,I use the inside button before I hop out but maybe there is dirty stuff in the lock?

 

Lube the lock cylinder !

Worse case take it out and clean it real good!!

Then lube things up