We found that there are some design flags or problems when uploading the backdrop for printing
Please check the following errors and revise.
Please save the file as TIFF, and provide us with a image to preview (screenshot or anything else)
(2)
[File(s) not flattened]
Opening your file(s) produced warnings. Layers must be flattened
before saving as TIFF for PC. This ensures that your image appears
fonts appear as intended, for example.
* Do not send .PSB. Please be sure to flatten layers and save as TIFF.
(3)
[File(s) in incorrect color space]
The color space or color mode of the file must be set to CMYK/8. If
submitting a file set in color space RGB, there may be a slight color
shift when printed.
* Please change color mode to CMYK/8, check your colors and re-upload.
* Zip or Archive after saving, or save with LZW or Zip option in Photoshop.