P0115 Fault code

I have p0115 fault code in my vehicle for a long time. Even if I delete it, it immediately gives the fault again. My temperature indicator works normally in the vehicle. I still bought a delphi brand sensor and installed it, but this fault code is not cleared. It comes to 90's, no problem, but it always gives the fault whether the engine is cold or hot. I couldn't find a solution. By the way, there is a temperature problem in the vehicle. There is no problem while driving, but when you squeeze the vehicle, the temperature rises up to 110 and does not fall down. The thermostat is new. changed. There is pure water+antifreeze in the vehicle, but I could not solve the overheating problem or the p0115 problem.

Update: I just made my measurements. 4.9v is coming to the socket, no contact, I did a little stress test socket and cables with it, but there is no change in voltage. When I measure the switch, it gives 0.97 ohm resistance for 68 degrees water. To verify, I applied a resistance to the 0.97 ohm socket and it gave 68 degrees in the obd and the indicator. In short, there is no problem with the socket and the switch, but the fault code is not cleared.