Poor service and client communication

So service at istore eastrand mall what service done my upgrade on 20 november after waiting since 20 september for my iphone 16 pro max today 21 december came back to the store to sell my iphone 13 pro max 1TB only to be told i only had 30 days it was not told to me the day i did the upgrade service really pathetic as i am a client with istore for years past year really was not a pleasure to do business with istore at all