Why do you get someones eles's problem when you send in air craft for repair instead of fixing the one you send in and sending back

We are terribly sorry for reading your frustrations. I tried pulling up your case (CAS) using your DJI Forum account. May we confirm if you are having issues with your Mavic Air 2 drone? Kindly let us know full details, please? We'll try our best to help. Thanks in advance for your patience.

it will not return to home any time I try to rth it will go to my rth hight at 283ft starts back and keeps jumping up about 25 feet levels out for about 3 seconds and jumps up again over and over until it reaches my max hight of 389ft then is stops and hovers if i lose conection I wont be able to bring it back Ill bet that is why last owner sent it back i've had this problem ever since i got it