what can it be if I have greenhouse gas refilled and only a cold pleasure of a few months ha

Hi, what can it be if I have air-conditioning gas refilled and only have a cold pleasure of a few months? I was once again so naive to believe that only because a workshop of Google got five stars that it was good, I was there last summer and the boss of the workshop, literally he told me that there were no leaks, exist because the car was accident-free. So I had air-conditioning recharged for 130 € and the air-conditioning also worked first, This is only for a very short time?? I was at another workshop today, which also fills up gas, but not looking for leaks. The colleague told me that in 80% of the cases the climate compressor is broken and in 20% of the cooler. Is this in your opinion dangerous half-knowledge or can be relied on. Mini Countryman built 2016 / 90 HP diesel. Key number 0005 BBV LG