The Cooling System Was Flushed And Topped Off To Remedy The Heat Problem ?
Was The System Low On Fluid Prior To This ?
Was The Cooling System Pressure Tested At That Time ?
Recheck the coolant level, again. Check in the recovery bottle and if it has a radiator cap, the radiator.
I think it’s possible that you’ve got air getting in your “closed” cooling system (and coolant getting out). This can happen externally to the engine or internally.
Some of these vehicles had problems with intake manifold gaskets leaking. Check your oil for condition. It should look like oil and not creamy beige (mixed with coolant).
Who flushed the coolant ? I’d take the car somewhere where the people working are familiar with the topics that I’ve discussed, here.
CSA