My wife got back from picking u g of kids from school on Thursday and the middle lap belt on the rear seat had stopped working. Digging around, I've found a 20p, a 10p and a 5p piece in the slot the strap goes into, as well as a round notelet thing tangled up in the mechanism (

). It must have fallen out of one of the kids' pockets (

). I tried vibration in both the horizontal and vertical (ie/ lifting the seat up into the hinged up position) but no joy.
Any help or suggestions on how to deal with this would be very much appreciated.
Thanks
Andrew