If a car seat belt fails to retract, pull it out farther and release it. If it won’t come forward, it may be twisted or jammed; pull hard and try to remove any twists or impeding debris.
If the belt is still jammed, examine the retractor (you may have to remove a at cushion or trim panel to get at it).
Poke a thin screwdriver into the spring side of the case and push the release -a bar, a ratchet, or a hanging weight -while pulling on the belt.
Once the belt comes free, pull and release it a few times. Spray silicone lubricant into the belt’s mechanism to help it run freely. Do not remove the retractor case. Any further repair should be done by a dealer or a licensed mechanic.