Hi, @Denma, I have not had any problems with mine, but if yours is having this issue when it is only 4 months old, then you should definitely get in touch with Fitbit Customer Support on contact.fitbit.com. If you get in touch by email it can help if you privide a photigraph of the strap and your receipt if you still have it. Customer Support will take it from there.
Sense, Charge 5, Inspire 2; iOS and Android
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