Chainsaws

I tried to register my PLN1514 but am unable to find a serial number anyplace on the unit. There is no "SN" and when I called the 800 # they said it should be in the form of a group of numbers with a letter in the middle. Nothing like that is anyplace on this unit. The sticker with the model number on it has lots of info on it but nothing that fits the format I was given. (see picture)