@adlinix, it looks like permissions to me. This is what the role for your service user should look like in vCenter:
From the Global group, check:
Cancel task
Diagnostics
Log Event
Set custom attribute
Settings
The entire set of privileges for the following groups should be checked.
Alarms
Datastores
dvPort Group
Host
Network
Resource
Scheduled Task
Tasks
Virtual Machine
vSphere Distributed Switch
In addition, you must also have the following objects and new role in place:
Datacenter: At the Datacenter the CloudForms Management Engine (CFME) (formerly EVM) user/group must have at least the read-only role at the Datacenter level (Not Propagated) to be able to see the datacenter. Without this access, relationships cannot be made. Specifically, the datastores will not show up.
Cluster: Each Cluster that the CFME needs access to must have the new role assigned and propagated.
Folders: Each Folder that CFME needs access to must have the new role assigned and propagated.
Datastores: Each Datastore that CFME needs access to must have the new role assigned and propagated.
Networking: Each vLAN or Port Group that CFME needs access to must have the new role assigned and propagated.