Heat works one day but doesn't the next on 1995 Oldsmobile 98

So I have had the car kinda checked out the heater core flushed out. One day I will have really good heat but when I shut the car off then turn it back on it doesn't work or gets colder. The blower is working just fine just no heat sometimes. The temperature gauge is at about 200

Asked by for the 1995 Oldsmobile 98
Needs to be kinda checked for a problem in the hvac control head or an actuator to the heat door inside the heater case.