This has been explained in the past but here's the short version.
As the interiors are printed separate from the covers, sometimes the process to combine them don't work out well and the printers have to manually combine the covers, as they have a quota of books to do and they can't afford to scrap the ones which didn't have the covers put on correctly.
Yours is probably one of them. If grading, CGC will give it an universal grade assuming nothing else is present to warrant another label.
xoxo
greggy
