Antifreeze is going into reservoir but not coming back into radiator.would be the cap?
I agree. Either the return hose has a hole or is leaking somewhere. You need to find it and fix it or else it will cause your cooling system to be perpetually low on coolant, which isn't good for the cooling system or the engine.Most likely a small leak in the tube or attachment to the tank. Allows suction to be broken as the radiators cool.