KIA Motors

I purchased a 2019 kia Optima S in September, almost immediately I noticed a popping noise coming from driver side rear, I have taking it to the dealership over 9 times, now the car has been gone since march 18th and its now may 1st, so I am still making payments also. A field tech from the manufacturer has been here twice, they have welded and taking the parts off the car and back on, and they still cant fix it, I have complained and exhausted all efforts with kia, its my first time ever buying a new car and now 40, 000 of the price on the car has been a waste, I can never get ahold of any one at the kia manufacturer { case manager} I leave constant messages and so all they have to do is give a new car I don't get it, never do this again !