A/C clutch frozen..what causes this? how much to repair?

I have a 2000 Mazda Protege and apparently the A/C clutch is frozen.
This happened less than a week after a radiator flush at Jiffy Lube
and I'm wondering if they did anything that could have caused this.
From what I've been reading this is going to cost at least $1000. Does
this seem right? I might have to live without A/C if this is the
case. Any info is greatly appreciated.

Jen Bennett

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