Good luck getting it back any time soon...
It took them 19 months to pay me back mine, when I overpaid (funny how they want it back immediately if you underpay, isn't it), and it also took them 5 years to get their records right that I wasn't employed full-time by a company I worked for for 8 weeks during a summer holiday from Uni. Every year, they sent me the same documents asking for my full work-history (and I mean FULL - dates started/finished, wages for the past 5 years, etc), I ended up going in there and making them contact this company while I was there, to confirm that I wasn't listed as employed by them full-time - they then changed the records while I was there, problem sorted!
