AC Compressor Clutch Not Engaging, Some Things To Try

Never had any trouble with the AC in this 2004 E-250 until recently. It's always been cold, but this time, it wouldn't cut on or the clutch wouldn't engage. Usually, if you're low on refrigerant, or have a leak, it would at least cut off and on. This one just stopped working. Took it to a shop and they said the compressor was bad that it was making noise and didn't know how long it would last. They put refrigerant in it and said when it goes out, bring it back. Well, it stopped working in a couple of days again. Never heard any noise from the compressor, so I decided to put my gauges on it. No refrigerant, zero. To see if there is any leaks, I pulled a vacuum. It held, no leaks. This tells me that it was most likely overfilled and the pressure relief valve opened up. Had this happen once before on another vehicle. Found the pressure switch and put a paper clip in the connector to engage the clutch so I could put refrigerant in it, and the compressor didn't engage. Unplugged the connector at the compressor, cleaned it with electrical cleaner, plugged it back up and it worked. Put leak detector and refrigerant in it and it worked. Next day, it quit working. Put my gauges on it and had refrigerant and no signs of leakage from the leak detector. Decided to change the pressure switch, still didn't engage. Found the relay location for the AC and with the engine running and control switch to MAX, you can feel the relay clicking when you plug and unplug, which tells me the relay is working. Checked the connector on the compressor, cleaned it again, plugged it back up and it worked. Decided to change the electrical connector for the compressor. Still didn't work. Everything I'm doing is telling the compressor to kick on, but isn't. Decided, on a last ditch effort, to spray the electrical connector cleaner all around the clutch on the compressor and it's been working now for a couple of weeks with no issues. Hope this helps someone! Thanks for watching!