I think the £48 predates the loss of the farm/house/barn and was some kind of income top up. She says Moth couldn't work because he was ill, and it implies she wasn't working either, if their only income was from their barn. She says that they needed to stay in the area for that benefit, but couldn't, so they never told the DWP they were no longer living at that address, just arranged for their post to be forwarded to Moth's brother's house. So the DWP or whoever still think they're living at the farm.
She also is careful to point out that they refunded everyone who had a booking at the farm.