Samsung watch and Apple phone

Hi

ive read all about pairing the watch to the phone via app, wearable and health. Sync is on in the settings and the steps from the watch are appearing on Samsung health but it’s still not recording all steps in my iPhone health which in turn automatically updates MyFitnessPal.

I’m then adding them manually in steps on the iPhone health but MyFitnessPal only seems to records the steps made via the phone only and not manual data.

help