You might consider having a chain type auto parts store (AutoZone, Checkers, Advance, etc) scan the car to see if any codes are present. They will do this for you free.
The car is 4 years old and there may, or may not, be an applicable warranty issue even if a code(s) pops up showing a problem. It all depends.
Let me add this. You the customer deal with service writers and service managers at the dealership. Very very few of these people have any mechanical expertise to speak of and rely on words to get through the day. A lot of these words are a combination of utter BS, placebos, and sometimes flat out lying.
I’d get the car scanned at a parts house and then post back with any codes that may be present.
Please understand that I’m not tarnishing all service writers/managers as being incompetent weasels. There are some good ones but in my experience the percentage of good ones falls into the low single digits.