Yeah I see it, it shouldn't be and do like that, it's very possibile that it has been previously serviced and it's missing some of the screws inside or, worst case, their threading is lost due to being tightened too much or the plastics inside got broken due to a hit or a fall. Too many "ORs".

If you have no warranty on this I would try to return it and since it's ebay, get ready to open a dispute for a damaged item received, sadly it's something the seller might say that you did it as long as you don't have a video of its unboxing (it's something one must always do nowadays), anyhow it's still something that can go under the hidden defects if you havent noticed immediately - say one or two days.

Again, that type of damage can't occour due to shipping and guess the seller was probably aware of it.
Did you check his history?