Check engine light on and code120308

the code #120308 boost pressure control, plausibility: pressure too low, I would start by checking the turbo tubes and boots to make sure they are in good shape with no leaks. If okay I would check the turbo main shaft endplay, if excessive I would replace the turbo. Here is a guide to help you see what I am talking about. Also, I have left instructions on how to change out the turbo in the diagrams below.

https://www.2carpros.com/articles/how-turbo-chargers-work

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.