[amazonechocontrol] switches from Online to Unknown and back all the time

Hi,

my amazonechocontrol is changing from Online to Unknown and back all the time:

Thing 'amazonechocontrol:smartHomeDevice:amazonAccount:xxx-xxx-xxx-xx-xxx' changed from ONLINE to UNKNOWN: State not found
Thing 'amazonechocontrol:smartHomeDevice:amazonAccount:xxx-xxx-xxx-xx-xxx' changed from UNKNOWN: State not found to ONLINE

I found some hints, but i don’t find a solution until now:

Any hints?

It happened also to me.
If I remeber well I unistalled the amazon binding and cancelled all the associated things. Then I reinstalled all.