How come car continues to overheat after multiple repairs done?

Bought car used from dealer on sept. 7. Honda Civic 03 EX.
I took it back multiple times and they replaced the thermostat with a plug as well.
Head gasket and just go the car back yesterday from getting radiator replaced. Also I replaced the radiator cap myself.
The car continues to overheat after driving for some distance and I stop on a red light or leave car on drive on idle or parked. Once I start to move the car again the needle starts to go down showing car cooling down. How come this still happens after getting most of the repairs that would cause overheating?
Please help cause I will need to drive to barstow this weekend from Los Angeles.
Added (1). they checked water pumps and no problem either.
I see the reservoir tank starts to fill up from overheating. I dont think it is the water pump as they been cheked.

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