Non-PRO Swedish to English Tech/Engineering Printing & Publishing

Hello

I can't give any real details as it is confidential

At first, I thought this was a typo for 'präglingsfel' (really confusing)

but the 'präglingsfel' will appear on a voucher and is discussed with the printer and customer (and appears many times in the document)

So now I think it is some type of watermark except that the word in Swedish would be 'vattenstämpel'

And there are NO hits on Google for 'präglingsfel'

Any ideas please how to translate this?

Thanks