I am writing to formally report a serious issue with my 2021 GMC Yukon XL. The vehicle has developed multiple severe problems, including: a¢Significant loss of engine power a¢Noticeable engine knocking noises a¢Transmission slipping while driving a¢Transmission movement even when the vehicle is at a full stop These issues not only impair the performance of the vehicle but also raise serious safety concerns. The loss of power and the slipping transmission could lead to a dangerous situation while driving, placing both myself and other motorists at risk.