Hello, it could be damaged inside it needs taking off the van and unwinding.
We were in greece and packing up to leave we found our fiama would not wind in... what a day, hubby took it off and we had to travel all the way back to france with it in the van.
we had it repaired in Italy at the fiama shop, we would be interested to know how much they charge in the UK for the repair. They changed the sheet and quite allot of the mechanical bits and put all back together and put it back on the van for us, works a treat now. Hope you get it sorted