You have reinstall the head gasket. It has been not tighten enough or damaged. Anyway the replacement was not done properly.
it is normal, when the coolant is hot and pressure built, the pressure cap allows the coolant to drain to reservoir to reduce pressure in the cooling system But, if it continually does this whereby the reservoir overflows and the vehicle overheats due to a lack of coolant actually in the radiator when cool, there may be an overheating problem or blown head gasket on the engine.
Tough to narrow it down with such little detail, but it sound like your car's thermostat may be malfunctioning and not controlling the temperature correctly.
your headgasket is blown
It can if it is stuck closed the engine overheats causing hot air ( steam ) to flow backwards to radiator cap which releases and blows steam pressure into recovery reservoir which starts blowing out the coolant in the reservoir making a puddle on ground.
As time passes water in the fluid evaporates and needs more so it Will suck it out of the overflow. It Will also dump it into the overflow if it overheats.
blown headgasket
You have a blown headgasket.
You must check the coolant level in your radiator and reservoir. Low coolant levels can lead to overheating. If it's low, you may have a coolant leak that needs to be repaired. Good luck!
The coolant has oil in it. Possible causes are a failed headgasket, or a leaking oil cooler,
white smoke from coolant usually indicates oil in coolant,this usually means a blown headgasket
Remove the coolant reservoir, flush it out, reinstall it and refill with proper coolant.
It depends on how fast it's leaking and how careful you are about keeping it full of coolant. If the engine overheats, even once, it can result in a warpedhead, blown headgasket and possibly other problems.