I bought an UP Mini 2, pre used and the guy shipped it to me without securing the innards’. The platform moved about during shipping and broke the plastic holders for the two vertical rods that the platform moves up and down on. I rebuilt them and reinserted the rods and platform. However the up/down does not work, I am sure I have not connected the drive belt properly. I can’t find any breakdown drawings that would show me how this belt connects. Can anyone help, even with a pic of how belts are connected.