An LCD screen works essentially by moving three ‘doors’ that let the backlight shine through. Each door lets one specific primary color pass through it.
Stuck pixels have problems with one or more doors, so it is possible that when the monitor is asked to change the color of a certain pixel, the doors move to an imperfect position, and then when the color is changed again, the doors move to a different, but still imperfect position. In both cases the pixel responds, and yet the color will not match the request.
Really there is no guaranteed cure for a stuck pixel so if you can’t live with it, then your only option is returning the monitor.
Some shops will take back the monitor no matter what (Amazon most notably), others will only honor the return depending on the policies set by the manufacturer.
The manufacturer may state that one or more stuck pixel is acceptable tolerance for their product.