wondering if I'm not compatible with FitBit?

[snoonian]

I'm hoping it's me, and not the FitBit... I seem to be having a lot of problems such as the HR monitor not rising to the correct heart rate during exercise, not recording exercise or activity, not syncing properly (it's always about a week behind and some things sync, and some things don't show up at all, like exercise time). I've tried chat support, phone support, replacing the device, restarting, logging out, alternate arm, varying the position and placement of the watch, varying the tightness of the watch... nada.. I can't seem to get it to work properly.  I've read all the troubleshooting, and tried everything... just about at my wit's end. anyone else out there finding similar issues? kind of a bummer because I love the size vs the Apple Watch, and the simplicity of the features. but not really worth wearing if all I can do is check the time. 

[WendyB]

First off is your phone on the supported list?

Using Exercise mode will insure you capture the activity instead of relying on Smart track

How to customize exercise modes
You can have up to 7 on your device. Make one Workout mode for activities that are not list. Then you can rename afterwards. Some might need a custom one added