Exchange 2016 does not Update Offlineaddressbook any more

Hello!
Not sure what I've done, but since a few days my OfflineAddressBook is not updated any longer.

When I use the Command

Get-OfflineAddressBook -Identity "Offlineaddressbook" | Format-List

I can see "LastTouchedTime" which is 12 days old.
I did run:
get-offlineaddressbook | update-offlineaddressbook
which doesnt return any error. But the "LastTouchedTime" doesnt change.

What can I try to do?