CBCS book is graded lower after return for label fix

Question.... how does a book lose .5 of a grade, being cracked open BY CBCS, to have the label fixed because THEY messed up and forgot to denote that it was a .35 cent price variant. When you specifically sent it back with them telling you that it would not be regraded, but just the label fixed, AND that the fixing of the label would be FREE...... Well, that happened as I sent back a CBCS 8.0 Cap 214 .35 price variant, that THEY forgot to denote as such, to get the label fixed (for free) . Instead THEY cracked it, regraded it (it's now a 7.5) And CHARGED me for the pleasure on something that was supposed to be a N/C label change. . I would have called customer service, but, being at work and not getting to open my box til a few mins ago they're closed, this is my only outlet other than festering all weekend, and still likely not getting this fixed properly.