The Fitbit Alta smart wearable by Fitbit was released in 2016. It features a tap-activated display screen that is slightly smaller and thinner than comparable models.
Might be worth cleaning the contacts on the Fitbit and the charger with some IPA, general skin gunk can make the contacts dirty so they won't make a connection.
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Make sure it is on the charger correctly.
mikeyd123 さんによる