Welcome to the Fitbit Community, @Amoz.
I am sorry to hear your Charge 3 is not vibrating. I am here to help. I've shared your post with our Support team and they've mentioned that you already have a case with them. I know they will be glad to help you out and provide a solution, please keep an eye on your inbox.
Meanwhile, please find our helpful tips in this help article: Why didn't my Fitbit device alert me?
If you have any questions, feel free to let me know.
Want to discuss ways to increase your activity? Visit Get Moving in the Lifestyle Discussion Forum.
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