The last couple of days Strava sync hasn’t worked. On /strava I get 403’s on a lot of .css and .js files regarding datatables. 
Hi René, could you send a note to support@xertonline.com with your username? The team will look at it…
It started working again it seems - and I was able to initiate a sync (using my mobile device (not the app)). However, the synced rides does not show on my Progression chart - and my Threshold power and 6 minute power has not been updated.