I am sorry to hear you are having trouble with your pendant. Sterling silver will tarnish naturally overtime with exposure to air and moisture. The good news is that it can be easily cleaned with a silver metal polish, we use Flitz Polish, and a microfiber cloth or jewelry cloth. You can find special infused jewelry cloths at most jewelry and department stores. We recommend that you do not wear your necklace while showering, swimming, working out, or sleeping. Moisture will very quickly tarnish the silver. We also recommend that you regularly polish your pendant. If you wear your necklace everyday, you should wipe it down with a cloth once a week to remove any oils or built up tarnish. If you find that the tarnish absolutely will not come off with the polish, please let us know and we will work on getting you a replacement or refund.