my top gasget was replace the oil and water does not mix in the engin only in the water bottel we did flush the system many times but after a day it start mixing again in the water bottel.
There are only two possible places where oil and water can come in contact: Either the oil cooler or the engine. Since you don't have an oil cooler there is only the engine left. Your statement, that the oil and water doesn't mix in the engine, strikes me as odd. How else should the oil reach the water, if not in the engine?
Since you stated that the gasket got replaced, I would go back to be shop that did it, to let them fix that, as most likely they didn't do it right (Didn't skim the head?).