My van's fans are suddenly turned on and the temperature's pressure gauge is disabled. On top of that, a script warns that there is an engine overheating. The thermostat and temperature sensor were replaced, it worked better for two months but the problem is now back. What might it be?

Good day, I have had to replace CTS(coolant temperature sensor) (several times) and thermostat(once) in order to stop my radiator cooling fans going off full blast and not turning off after shutting engine off. I have enough coolant; truck does NOT have relay for fans, it has fuses, and they are good. Please advise at convenience and thank you.