I was told by a mechanic that the oil pump is seizing striping the worm gear

What is your question?

This is the second time in a week that my car is back in the shop for the same thing that happened to the worm gear at the bottom of the distributor and cam shaft the first time they replaced just the distributor. IT cost me (430.00) now they are saying that the oil pump is causing this to happen that for $650.00 they will replace it. Today when I broke down I removed the cap and seen that the rotor was not moving so I knew that the same thing happened to this car again. please help I never heard of an oil pump causing this to happen