Hi Gavin and welcome to JustAnswer,Thank you for the question and your patience. Should you still need assistance for information purposes only...Initially, have you tried power cycling; i.e. turning On/Off a couple of times?
How about placing an active vacuum hose over the lens while power cycling? It may require a sort of paper funnel to fit the vacuum hose over the lens. The idea is to draw out possible dirt, sand or foreign particles that may likely be jamming against the fine gears of the lens assembly.
Great! Good to hear that the issue has been resolved, congratulations.