Charge 5 not tracking zone minutes when in cardio zone

[kitkat8675]

My Charge 5 doesn’t read my heart rate correctly when it goes above 165. It drops down to 100 all of a sudden when My heart is beating like crazy and the elliptical says 178. Anyway the heart rate tracker says I was in the cardio heat rate zone for 5 minutes but no zone minutes were recorded. It shows cardio heart rate even on the zone minutes graph but still doesn’t record it. 

Moderator edit: format

[DavideFitbit]

Hi, welcome to the Fitbit Community forums, @kitkat8675.  

Thank you for sharing this information regarding the inconvenience that you've been experiencing with your Charge 5. 

Keep in mind that you earn Active Zone minutes for time spent in the fat burn, cardio, or peak heart-rate zones. Heart-rate zones are personalized based on your fitness level and age. Before considering other options, heart-rate tracking can be affected by several factors including air temperature and device location on your arm; please make sure to follow the steps in this article to improve accuracy. 

In the meantime, you can try restarting your device following these steps, and in case this problem is related to the app, you can follow the steps listed here below as well: 

• Log out from the Fitbit app. 
• Clear Cache and Cookies for the Fitbit app on your phone's settings. 
• Restart your phone. 
• Log back in to check if your data is shown properly.  

Hope this helps, I'll be around.