A common problem caused by large aperture telescopes and having good seeing conditions is that the exposure time though a particular filter can over-expose the sensor if the target object is particularly bright or the exposure time is too long.
Each pixel on a CCD sensor has a maximum light detection capability. Once this is reached, then the pixel is said to be saturated and the additional light will overflow and leak to the adjacent pixels. This causes an artefact that unfortunately cannot be fixed.
The solution is to use shorter exposure times to avoid saturation.
Unfortunately, we are not able to offer refunds if your images are saturated. You should use the appropriate exposure time depending on the brightness of the object and the size of the telescope.