Maybe you have already discussed this with Finnair, but just in case:

Earlier this year I booked a return ticket to Finland through this website, and when I got my ticket my name had morphed into "first name ms" (no spaces between) and "last name", i.e. Janems Doe. I could see the exact same error on Finnair's website when accessing my booking.
I called Finnair and asked about this, and apparently something had gone wrong in the transfer of info from the online form to ticket, so it looked all weird. But the person on the line confirmed that my name was correct in their database, and when I printed my boarding pass it was all normal again.

So if you're not sure you typed the names wrong on the forms, ask Finnair to confirm what it looks like to them. Otherwise, good luck trying to get the fees reduced!