My fit bit is not tracking my bike workout not counting the miles or steps

No manual available. The generic manual in the link might be close enough.

https://www.google.com/search?q=Avia+2+function+pedometer+manual

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It will be the same procedure as replacing the belt. They usually has a mechanism for tensioning the belt. That needs slackening off first.

You could contact a seller, or watch the videos

Total Gym CycloTrainer for intese Cardio Workout

Total Gym Direct https://totalgymdirect.com > shop > total-gym-cyclotra...
Easy Low-Impact Workout - simply lay back and cycle with the glideboard anchored at the bottom of the rails. Strengthen your core; ..
US$399.95 · ‎In stock

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  Total Gym CycloTrainer for intese Cardio Workout

  https://totalgymdirect.com > shop > total-gym-cyclotra...
  Boost your cardio workout with Cyclo Trainer for Total Gym! ... shavings from a rubber belt (presumably a belt that is used to increase the resistance?)
  

There isn't a lot of difference between them. Cardio is all about getting you heart rate higher so Treadmill or Bike is often down to which you personally prefer. You could also use a rowing machine to get the same cardio workout.
The biggest difference is mostly which muscle groups your using to pump up your heart rate.

I think the problem on that is only the pedal sensor.
The sensor will count your every steps. And it will also read the distance of your workout.
If the sensor is damage you can't get any readings of your steps. If that the case you need to replace new sensor.

I would like to recommend you , go first to the doctor, by your high pressure, and then you will have a good view to take exercises.

God bless you

my nordic track 1000 stops several times during the workout. I can step to the side and the belt may or may not start back up. The display continues to display the set machine. any suggestions?