i have a Hauwei P8 lite but i cant bluthooth with my fitness tracker

There is a known issue with the Huawei phones:

https://en.discussions.tomtom.com/spark-and-spark-3-runner-2-and-runner-3-473/tomtom-runner-3-not-pairing-with-my-huawei-p8-lite-1029835

You will have to sync by computer until it is fixed (if it is at all - TT has left the sports watch market altogether and is not producing any new devices so they may never fix it).

I hope this helped answer your question. If so, please mark it as a solution so others can look for it if they have the same question.