Fitbit Product Experts Alumni are retired members of the Fitbit Product Expert Program. Learn more
Fitbit has a troubleshooting guide for charging issues at Help article: Why isn't my Fitbit device's battery charging?
If those tips don't work then, as it says at the end of the guide, it's probably best to contact customer support. If they can't fix it then they can check on your warranty status and advise on your options.