Yes, you can get your belly button repierced if it has been rejected. However, it may not be advisable for several reasons.
If you are experiencing rejection due to the metalé•Ť, you may react negatively to it. You should consider using non-irritating materials like surgical steel, titanium, or gold.
It is important to wait a while before getting a new piercing to allow for proper tissue healing. This is typically at least a few months but can vary.
Rejection commonly occurs early on in the healing process or after several years since the previous piercing was removed.
If your belly button piercing has a keloid or large scar tissue from a previous rejection, it may be safer not to attempt a re-piercing in that area.
You should research and find a piercer who is reputable, experienced, and whom you can develop a good rapport with for the best outcome. The piercer should be willing to discuss your options for materials and piercing locations with you.