Turbo underboost
P0299 means the turbo did not make the boost the ECU commanded.
The car feels flat under load. A leak in a boost hose, a stuck wastegate, or a worn turbo can all sit behind the same code.
Inspect hoses and clamps before condemning the turbo. The P0299 page lists those checks.
A trouble code marks a condition to test. It does not by itself prove which part to replace.