Do you have a way to test the air temperature coming out of the AC ducts when the compressor is running? If you do the air temp coming out should be 15 to 22 degrees cooler than the room air. If not you have an issue.
Second question do you notice an oily substance on or near any of the AC vents? Just a guess, but if you do then you probably have a blown compressor that is overheating and shutting down.
Marc & Jan
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