Car over heating on incline Options

[Oreo20]

Weird thing happening plz help
Current temp in Houston almost to a solid 100 degrees F
Driving on the high way speed limit is 75 mph doing 80 mph
Ac set to on 2nd setting blower
Car temp rising when going up inclines steep highway up and downs

Temp back to normal when I turn off ac
And normal temp when driving on road ways non highways with ac on

Is there something I should look at
Or service /:
I have a feeling it’s just way to hot for this poor car
But something might need servicing

[Box]

Check to make sure the radiator and condenser fins aren't crushed or blocked off. Outside of that make sure coolant levels are proper and that the radiator cap is good, could go a step further and make sure the A/C system is charged with the correct amount of refrigerant.