This happens a lot when people copy TeamRaiser events from previous years. When you copy the event the previous event association field does not change automatically, and so your TeamRaiser may be linked to an older even than you want (thus skipping over the event from the previous year). To fix this:
  1. Fundraising > TeamRaiser > "Edit" next to the TeamRaiser in question
  2. On the first page, scroll down to #7 "Previous Event Association". Choose the event you would like to link with (in this case the one from the previous year) and click "Next"