2 devices I’ve got cannot be decommissioned. Devices were never “fully” registered (the UI says it’s waiting for inventory data from the device for a couple of days already) but cannot be decommissioned. No error message though. (BTW, when querying for the list of devices using mender-cli, these 2 devices do not show up - if that helps…)
Do you have any screenshots?
Does it show any button for “Reject” the device? Or does it seems it was already “accepted”?
As you are describing it, potentially it could be an issue on our side, so let us look there as well.
I will ping you back as soon as possible.