Step synchronization error partly solved ... can you help please?

Hi goodmorning.

Question/problem with my wife her Fenix 5S.

On the 12 of november half day the Fenix stopped synchronizing the steps / intensity minutes / sleep etc etc.

Tried serveral options; only removing the watch from GC on Iphone, and installing it again offcourse, solved the problem partly.

It only has synced the steps of today and not from 12 nov until yesterday. 

When I check the watch all the data is availiable.

How do I get those day also synchronized in GC? 

Anyone an idea?

Thanx for your help

Edo