While you can’t put a ‘Completed Order’ back into the ‘Rented Out’ state you can make another copy of the Order and put that in the draft state and then delete the original Order. To do this:
1. Go to the Order Details page of the wrongly returned Order and hit ‘Clone’
2. Once you have cloned your Order, go back to the original Order and ‘Void’ it.
3. Once the Order is voided you will now see the option to delete the incorrect Order.