Whirlpool 20RBD4 fridge part not getting cold enough

Hi

I have a Whirlpool 20RBD4 American style fridge/freezer, less than 2 years old. The freezer is fine. The fridge however is not getting cold enough. When I adjust the slider for the meat/veg drawer, the vent shows signs that the air is coming through. The 6th Sense light is on permanent. I’ve turned the fridge side down to 2 degrees, but it doesn’t appear to be getting any colder. I think it may have been like for a while, due to milk going off, but is more noticeable now the weather is warmer. Is there something else I can check or do I need an engineer? Any help much appreciated