If the Main and A/C are together [a double breaker], move the A/C to another breaker.
there should be room to install another breaker.
There is heat transfer in the double breaker, which will ultimately cause it to fail.
What you are describing is similiar to what happened to me and finally the main stopped working.
Walt & Lindy
2004 Ford 250 V10
2006 Cruiser CF29RK
Baylee & Shadow [Schnauzers]
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