no sleep movement graph

Since 3 days ago Garmin Connect App (Android) shows after synchronizing my vivosmart 4 no sleep time. After setting it manually and resynchronizing the vivosmart again (sometimes two times) it shows the kind of the sleep-phases but no movement-data-graph. Only the colored line at the bottom of the diagramm is visible. If I log into my Garmin Web-account I see the correct movement graph . Does someone observe the same problem? 

  • My device hasn't been recording any sleep data at all for the last week. 

    In fact, it only tracked sleep properly the first week I had it. After that it stopped recording REM sleep. I was too busy to worry about the problem and this continued for a couple of months. And now nothing at all. 

    I've spent ages fiddling around trying to resolve syncing problems too. I need to find the time/energy to contact Garmin. When my last device broke (vivosmart 3) I had to pay to send it back to be checked though (even though it was in warranty), and it took nearly two months to receive a replacement. Feeling rather demotivated on the Garmin-front at the mo, which is a shame because I enjoy using the devices when they work...