First, make sure that you are using the correct file type for your background image.

1. Background images should be .jpg, .png, or .bmp.
2. The file must also be smaller than 18 MB.
3. Images with transparency should not be used as backgrounds.
4. Finally, ensure that the aspect ratio of the background image is either 16:9 or 4:3.

If your image matches these requirements, but you are still not able to see it properly, try using a different background image.