I don't know if this will answer the question, but when I called Fitbit and expressed the issue, they said it's possible my Inspire HR was loose, or it became loose in the middle of the night. They suggested I tighten the band.
It's been a day and it tracked last night, so we'll see.
Thanks but I am sending it back for a refund 😀
Too much hassle trying to get it working
My old flex is 10000 times better to use 😀
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