How can I delete inactive device?

Hello! Is there a way to delete this inactive device? I don’t see any option to do this in device info.

http://i.gyazo.com/9e38fdb3d7a20c85938ad5f10efc8ba6.png

Please use the search option before posting.
Things like this have been explained multiple times already.

https://forum.avast.com/index.php?topic=160812.msg1153078#msg1153078

Yes, I know about this. But in my case the “Settings” button is inactive. Nothing happens when I press it.

Is it inactive for both devices listed ?

No, just for archived device (bottom).

Could it be it is a backup of the phone ?

I don’t think so. It’s a kind of ghost-device. Created in March, when I tried Avast Backup for the first time.
All listed backup categories are empty.

http://i.gyazo.com/e89a2721290c9791cb034ca4b6388b2d.png

Any solution?..

I suggest to submit a ticket about it to avast:
https://support.avast.com