Master lock problem

So, when I bought the little car for the daily driver, I switched the big Rigid box out of the truck and put in a smaller one. Now, about a year later, I go to unlock the box, no go. Key goes in won't turn, have lubed, but it has sat in a garage for the whole time, no rust or debris in them at all. Found the spare key, same. 100% sure it's the correct key. 100% The box is made to take these locks, it's damn near impossible to get onto them now, I have an email, and a contact us message to them, but they need time to respond. Anybody? I've had locks last forever and the keys work, I am stumped.
100% correct key. 100%, it never left the key chain.

 

Pop the hinges if you need to get in quickly

 

I re read my OP, pretty vague on the box description. My bad.
4 foot wide Rigid job box, had it mounted in my bed, it's fairly impregnable when both locks are locked on it, like now. I want to use the box without cutting and mangling it. I think I'm going to call a locksmith, see if he can get them both open.

 

Drill the cylinder or angle grind the hasp or big ass bolt cutters.

 

You Tube. There is a way to break the lock with 2 wrenches.