iPad could not be restored unknown error 4013
I have an iPad that won't restore. It is a 7th generation iPad that is a year or two old. iTunes says that it can't be updated and it must be restored to factory settings. When I try this I get:
"This iPad 'iPad' could not be restored. An unknown error occurred (4013)"
I was on a chat with Apple support and they had me go through the same restore process with the same result.
I have ensured that I have the latest version of iTunes. I have tried different lightning cables and different PCs, with the same result. I have plugged the iPad in overnight using the original Apple charger and cable.
Anyone have any other ideas?
Note that I can't go to an Apple store as the stores here (in Toronto, Canada) are closed due to Covid.