Charge 3 not tracking distance and pace accurately

[GermaineG]

The first time I used the exercise app for running I got accurate distance and pace. Since then, for a 30 minute run it gives me a pace of 20 minutes per mile, a distance of 1.54 miles and about 4000 steps. It should read around 3.3 miles and 5000 steps. I have manually changed my stride length and rebooted the Fitbit several times. Any suggestions?

Moderator edit: updated subject for clarity

[MarreFitbit]

Hello there @GermaineG, welcome to the Community Forums. Thanks for the details provided and for taking the time time to manually change your stride length and restart your Charge 3. 

Fitbit devices calculate distance by multiplying your walking steps by your walking stride length and multiplying your running steps by your running stride length. We estimate your stride lengths using your height and sex. Track one or more runs using on-board or connected GPS, we evaluate that data to automatically update your running stride length. For best results, run at a comfortable pace for at least 10 minutes.

If you prefer to measure your walking and running stride lengths, make sure to follow or to have followed the steps provided in the article: How do I measure and adjust my stride length?.

Note that when you're tracking an activity with GPS, Fitbit calculates your distance using GPS data rather than steps. If you begin moving before you get a GPS signal, the tracker will calculate distance using steps and stride length as described above until a GPS signal is found.

After reviewing this factors, please go for another run and see if the distance improves. 

Let me know how it goes, I'll be around. 

[GermaineG]

As I stated in my post, I have manually changed my stride length to reflect
my actual stride. I have also rebooted the fitbit.