I have had my Fitbit Charge 4 for less than a year. I'm having major issues right now. It is not counting steps or stairs, it is not registering my heart beat and it is not assessing sleep (which I assume is also related to the not registering heart beat). Many of the other functions are still working such as time, timers, alarm, weather, exercise (w/out heartbeat). I've re-booted both from settings and from the charging band, multiple times. I've synced with my phone numerous times as well. It started on Sunday and then it magically worked again for about a day and then about Wednesday, it stopped counting steps/heartbeat again. I used rubbing alcohol and toothbrush to clean the sensor. I've adjusted the band looser and tighter. A few weeks ago, I noticed a black line across when it was fully charged, I think it's called a broken pixel. Sunday, I noticed an additional line, and today, I noticed there are three total broken pixels. My last FitBit, the Charge 3 stopped working abruptly last summer (it was about 2 yrs old, I think, maybe a year and a half) and my mom bought me this one for Mother's Day. I was going to buy my husband a Charge 5 but if the FitBits aren't even lasting a year, I may have to go with a new brand for both of us. 😞
