Teams Phone Numbers Mysteriously Unassigned

Occasional Contributor

Over the last  2 weeks or so, we've noticed a handful of our Teams phone numbers which were assigned to users, become Unassigned.  We have no automation in place - everything move, add or change we perform with our phone numbers is manual.  The numbers in question have been assigned for months now.  It wasn't until my phone number was assigned to someone else that we realized the issue.  In order to assign a phone number that is already assigned, you'd have to delete the current user - which we certainly have not done.  Mysteriously, the phone number status changed from assigned to unassigned.  Has anyone experienced this?  We have Operator Connect through Pure-IP.  Thye don't touch our numbers once they are given to us in the Admin portal (or do they?).  My MS Premier ticket came up empty.  Apparently there are no audit logs for phone numbers, just licenses.  And we verified no change in license status at all.  

13 Replies


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Thanks Therese! I did open a case with MS. There are no logs, as it turns out, catch the history of phone number activity; though you can do so with licenses. We already verified that the licenses remained in-tact.

@dennyhanrahan Same problem. I thought I was going mad. Started 4-6 weeks ago now.

Long term users complaining their dial pads have disappeared. When I check Teams, the number has been unassigned.

I'm using Direct Routing via on-premise Session Border Controllers, so no-one else should be touching my numbers
That's very interesting...and unsettling! Did this happen with using Operator Connect? If so, who is your Operator Connect vendor? or did it happen with numbers provided directly by Microsoft? Thanks a bunch for replying!

@dennyhanrahan I'm not familiar with Operator Connect, but a quick Google shows these providers offer Session Border Controllers as a Service (SBCaaS) so our setup is similar.

We are using Session Border Controllers and Direct Routing. Our carrier is Optus.

We have reserved number ranges for each of our offices, and these number ranges are hosted by Optus. We pay Optus for our call charges (not Microsoft).

We are facing the same issue.  We do run Operator Connect but have been able to check and see there have been no changes through iPilot. It's very frustrating that there aren't activity logs to go back to on the MS side. We thought we've been going crazy since we asked MS and they said there is no way that should be happening.

Thanks MarcR727 for your feedback! I did get a root cause from Microsoft that it was a bug fix: The AD attribute OnPremLineUriManuallySet bit was false due to the bug. There was a bug in the legacy TAD cmdlet because of which assigning OC number did not set OnPremLineUriManuallySet flag.
Good to know, thanks Denny. I have a case open with Microsoft for this issue but they didn't mention that. I'll add your info to the case notes.

@wombattler Any further updates on this? We recently moved to teams calling and noticed this started happening.  Our Provider logged a job with Microsoft, but there has been no definite answer on the issue or solution. 

@BrendanNZ no further issues experienced here, after Microsoft's bug fix.

@BrendanNZ We are still seeing the issue (phone numbers randomly unassigned). I logged a case with Microsoft but then it didn't reoccur for two weeks, and they closed the case.


@wombattlergreat thanks Denny, much appreciated.