I want all my workouts in PerfectPace but Polar just syncs data from the day I set the conection up.

To get all all your past activites into PerfectPace you need to upload them manually. Polar only syncs your activites from the day the conection was set up. No past activites get synchronized.

On Polar’s page you can download all you data. This article describes how this can be done:
https://support.polar.com/en/how-to-download-all-your-data-from-polar-flow

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