@srinivasan38749 since you have already refilled twice and it seems to work for a short time, you do need to check for a refrigerant leak. I'd suggest that you get yourself a leak detector (something [https://www.amazon.com/Elitech-WJL-6000S-Refrigerant-Condition-Indicator/dp/B083XTT26M?source=ps-sl-shoppingads-lpcontext&ref_=fplfs&smid=AON8DME687K1&th=1|like this] ) and check your lines, condenser etc.