I think I can shed some light on Frouge's situation, but I'm also looking for answers. I've had an almost identical experience, where I was making regular contributions to a so called Flexable Spending Account (FSA) or Health Care Re-imbursement Account,through my employer up until the time I retired at mid-year. When I tried to get re-imbursed for a medical expense incurred just after my retirement,they threw "catch 22"at me also,explaining that the "use-it-or-loose-it" clause does not always mean that you have till the end of the calender year. The fine print in their "Plan Document" states that when you terminate ,your participation in the plan ends and if you have any cash balance, it can only be applied to expenses incurred before you terminated.Thats the Company's and Administrators position but I really wonder if it's what the IRS had in mind.The appropriate part of the IRS Code is Section 125,but I've yet to find a copy for myself.
The only good news is your contributions were made "before taxes" and dont show up as income.