Your description (partial) : "problem is , after 20 min of driving I’m loosing good amounts of coolant"
On a routine drive I got a low coolant light, strange because I never saw any fluid on garage floor or any other indications of a leak or problem. Topped coolant off (not a large amount) and it happened next time I drove the car, again no signs of leakage anywhere. With a lot of troubleshooting it turned out to be a simple problem. The "O" ring in the coolant cap needed to be replaced.