License Issue: One user, one computer, two seats taken up

I just tried to install DT3 on another machine and was told no seats available.
Checked My Account and I see that two devices are listed, but both are the same computer.
One is shown by the device serial number, with no “User” listed.
The other is shown by the device name, with me as the user.
Both show “Last Used” as today.
If I click on Edit, there is a delete button by the second one with my account, but not for the first with only the Mac’s serial number.
There are no other users logged in (and have not been for some time…the other accounts are for admin and testing purposes…this is in effect a single user machine.)

Can someone advise what’s going on here…and how to resolve it?

Do you have DT3 installed on multiple user accounts? If so, there was a change in the software recently which results in this situation. The solution is to go to the license section in each user account and disable the license, then re-enable the license in each user account.

Thanks for the note. DT3 is only activated on one account. (It’s of course “installed” in the apps folder which is visible in all accounts).

Have you connected to Ethernet?

On the computer with the two seats, yes. With the one I’m attempting to add, WiFi. (What difference does that make?)

If it helps I also had this issue connected to ethernet.

Do you ever use any Ethernet adapters for USB/Thunderbolt?

No. The computer with the duplicate seats has integral ethernet; the one I am attempting to license is on WiFi.

Do you use DEVONthink on this computer on multiple accounts?

No; While attempting to see what the issue is, I started DT3 on all (3) other accounts and verified that none were activated.
If it matters, the dupe licensed machine uses both Ethernet and WiFi.

What kind of Mac do you use?

iMac Retina 5K, 27-inch, Late 2015. Mojave 10.14.6.

Please contact sales - at -, they’ll be able to unregister the seats so that you could try again to license both machines.

Thank you, will do.