the mystery is solved

ordering receipts...

printer:  'you want it carbonized or just the ordinary?'

me:  'i don't want carbonized anymore...  it's no good...  i still have to put carbon for the writing to appear on the duplicate...'

printer, checking my old receipt:  'this is not carbonized...'

me:  'it is...'

printer:  'no...  this is just regular paper...'

me:  'that is carbonized...'

printer re-checks my receipt:  'it's not...'

me:  'really?  i ordered carbonized from you before...'

printer:  'you did?'

me:  'yes...  you said it costs more...  i said it's ok, at least, i won't have to use carbon anymore...'

printer:  'this is not carbonized...'

me:  'what?!  no wonder it doesn't work!'

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