Mystery water leak driving me crazy help please !

Guys i did everything posible ... gasket was changed year and half ago , did service 2 monts ago : water pump infold gasket cambelt all filters ... changed coolant cap with original one ordered from UK . I also used something for leaking radiator (eaven i didnt find anywhere wet from coolant ) temperature sensor no signs of leak also problem . Car preasure is normal i guess (when engine is hot)



Story is like this i do short drives 25 kms in that kind of drives in 100 km coolant will be from max to minimum ... 2 days ago i was driving total 300 km coolant is now near minimum . Problem is i always top up when i see that is droped so im not sure should i stop toping up and just see if it goes under minimum ?



Im realy starting to be desperate so any advice would be good ...



what i can tell that car is loosing coolant when its not working ( after drive when is hot) so when i park the car i can see coolant go down tomorow . What is tricky that after loong drive of 300 km i loose less then few short drives of 22-25 km ...



Also to note my mehanics did chek everything car is dry everywhere we couldnt locate leak place anywhere ... i readed every leak topic here and cheked nearly everything ...



Also to note no oil in coolant no water in oil ... everything is normal car drives normal heaters work , no water under drivers carpet ...



I literally lost idea what could i check or do to stop this ... any advice would be helpful thank you





and i used this it didnt help



i plan to buy and try this if i cant find another solution :(

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