Gas and Oil Home Heating Furnaces - compressor won't shut off

Hello this is my first post. Any help would be appreciated. I have a RHEEM model# RAKA-036JAZ it is 10 years old. I live south of Atlanta the temps right now range from mid 80s to the 60s. I have a ranch style house approx 1700 sq. ft. The A/C blows cool, has good pressure out of the vents and good suction at the air return grills. When the house reaches the desired temperature set at the thermostat, the furnace fan shuts off as normal but the compressor continues to run. At this point the compressor will start to freeze up. The only way to shut it off is with the circuit breaker. I have cleaned the coils on the outside unit. I have a clean filter in. I attempted to clean the evaporator coils but could not fully access it. I could clean it with a sprayer with a wand attached. But I don't know what chemical to put in the sprayer. (Help with that, too, please) The A/C has been used quit a bit this year already. This just started a few days ago. Why does my compressor not shut off? Thank you in advance for any help.

The contactor (relay) that turns the outside unit on is stuck or the contacts have welded themselves together. Either way I'd replace it. If your not comfortable around electric -call a contractor.

contactors should be changed when there is visible pitting and or burnt smoky areas around the points. a regular maintenance would have possibly prevented this. it is common for them to do this.