Cooling system

I replaced the temperature sensor with new one's and used a scan tool to read the sensor temperature. The reading is the same i.E Red lamp on at 94 degree c instead of 120 degree c.

I have a Hyundai new accent 2008 car, 1.6 l, 4cyl, fwd, manual 1.6l, 135000 km,
Because of overheating before, an over hole maintenance was taken and due to a little deformation in cylinder head, 2 head gasket are installed to compensate the cylinder head thickness after resurface it
The cooling system have 2 indicator lamps one blue for low temp. And the other red for high temp. After some weeks I found the red lamp on in traffic but didn’t in highways
By checking the cooling system
†Replacing thermostat, temperature sensor, radiator cap,
†Cleaning radiator (aluminum type) internally and externally, checking the coolant level regularly is detect no leaks
†Checking the electric fans operation are ok.
†Checking water pump impeller is ok.
†Checking by using another controller
†Checking by using instrument cluster and indicator lights panel controller
†Checking bad gasket and cracked head using block tester and test fluid it found ok.
After that I found the same state red lamp on in traffic but didn’t in highways
Using scan tool which indicate that red lamp is on at 94-96 degree c and radiator fan on at 96-98 degree c and code p0118 ( mean engine coolant temp. Circuit high input) so why red lamp