There are a few different ways that you can release the back seat belt, depending on the type of car that you have. If you have a button on the ceiling near the backseat, you can press this to release the belt. Some cars also have a lever on the side of the seat that you can pull to release the belt. You may need to use both hands to do this. If neither of these methods work, then your car may have an automatic release system. This means that there is a button or lever that you can push or pull to release the belt, but it is located in a different place than in other cars. To find this, look for a small hole near where the seat belt meets the floor. Inserting your finger into this hole should allow you to feel and press the release button.