Nothing Phone 4a clean dirty lens warning comes up when there is no dust or dirt on the camera lens.

I just bought the Nothing Phone 4a, I've been using it for 5-6 days. I've noticed this issue, the "clean dirty lens" warning pops-up when I open the camera app even if there is no dust on the lens. It doesn't happen all the time, just once or twice a day. I check all the lenses using a flash light, there is no visible dust inside. Is this a major issue? Should I send this for a warranty claim?