You could try one or more of the following:

1. Delete the device icon (e.g. after wipe or unenroll action)  before re-enrollment 

2. Tick the "Preserve Device Name on Re-Enrollment" in the Advanced tab of your Add-Devices rule.

3. Tick the "Enable Strict Android Re-Enrollment" option in "Enrollment Settings" in the All-Platforms tab,

Matt - I use the #2 approach ( what Raymond listed ) on my enrollment rules. I have had great luck with not getting duplicates. It is almost like your enrollment did a double dribble there.

Thanks Gents! I already had suggestion 3 enabled, but not suggestion 2. Hopefully that remedies any issues with future enrollments.

Any suggestions for remedying the devices already in this state? Selecting one of them automatically selects both:

Can you unenroll? Delete both and re-enroll and see if you only get one?

Interestingly the issue just seemed to eventually remedy itself. The duplicate device just disappeared after an hour or so, without any intervention needed. 

Hi Matt,

Even this problem solved by itself, we had this issue and you can solve it forcing the sync of the Mobicontrol Search Service. You can do this in the configuration of the Interval, pressing Sync Now. I guess, your server synched by it's normal schedule and your problem was solved.

Great point! I bet that was it considering that it seemed to resolve itself.