HEAT PROBLEM

my tool 2008 1.6hdi excuvite package. My problem is that the temperature is getting too high (without air conditioning). I took it to the master, he said that the thermostat is not original, he said, I replaced it with the original, the problem continues. When it is connected to the computer, it does not show any malfunctions. What I observed is no water reduction, the fan works in two stages, there is no leakage in the radiator area, the hoses are intact. We couldn't find the reason. I wonder if you have been through such an event and have you managed to eliminate the problem? I would be very happy if you could help. Indicator image in the link below

https://www.hizliresim.com/i0ilhic