The central AC unit during very hot conditions, above 90 degrees, will stop cooling the house, just will be recirculating air in the house. The outside unit fan will be running, but the compressor does not seem to be running.

However, when the tempature drops or turning off the AC Unit for a few hours, the systems will start working again.

We have had a service tech come out and check the unit, but they have not identified any issues. They did come out during the hot weather, they said they added some freon and it did work for a little while, but in a few weeks it has started again.
Are there other suggestions that we can look at to try?