Teams app not ringing reliably on incoming PSTN calls to iPhones

Regular Contributor

Tenant is upgraded to "TeamsOnly", with Micorosft Phone System and Calling Plans in place, and things are working for the most part, however, about 50% of the time, my users say that their iPhones running the Teams app don't ring/alert on incoming PSTN calls, but they do get a missed call notice.


I've made sure of the following:

1. the app is up-to-date

2. the app setting for "Always ring on this device even when active on desktop" is checked

3. they're not in "Do not disturb" status


FWIW, the legacy Skype for Business app for PSTN calling on mobile was equally unreliable - lots of missed calls, and Teams seems to be no different in this regard.


Is anyone else having this issue? What other things can we check to make sure calls actually ring as they are supposed to?




42 Replies

I have this problem on my Android too.

Pretty sure PSTN is still technically running off the same Skype for Business backend, hence why the experience is the same. I don't have any other suggestions unfortunately. Maybe check to see if the calls shows up in the new admin center call reporting to see if you can see anything there?

Not really @Chris Webb. Although the new Office 365 Phone System backend first became available through SfB, it's by no means 'old' or being replaced anytime soon.


I'm not sure what @Bob Manjoney means by 'the app setting for "Always ring on this device even when active on desktop" is checked', I think you are referring to the setting for notifications? not calls.


Have your users configured Teams to simultaneous ring their mobile numbers?


Yeah not Old, but still the same back end. The chat etc. is what I believe is on the new Azure stack. Obviously they've continued to bolt on, but the Teams mobile app should be much more reliable. How long ago did you change to Teams only mode? I know the PSTN stuff takes awhile to fully converge over to Teams.
I assumed that the app settings for notifications included incoming call ringing behavior. It seems to suggest this as one of the notification toggles is labeled, "Incoming Calls".

We have not configured Teams to simultaneously ring their mobile #. We just want the Teams app to ring on their mobile phone when someone calls.
Hi Chris,
We changed over to Teams Only mode about a month ago.

Ahh ok, should be plenty of time :).
I will say that often times restarting the phone seems to make the problem go away for a period of time. Having lots of apps running on the phone also seems to exacerbate the issue, so I'm certainly open to the possibility that it has nothing to do with the back-end, but is instead a phone or app issue.
Same here - just more iOS than Android users for this particular group, but it seems to affect both equally.

Silly me to assume that the settings for Android and iOS were on parity :)


Here's the Android app notification setting page:



And once again - this time on Android. Incoming call never rang, but immediately displayed a "Missed Call" notification. Arghhhh….however, I am able to reproduce it reliably by doing the following:


1. Launch/login to Teams.

2. Call into Teams app from PSTN - phone rings - terrific.


3. Tap the Android Square system icon (lower-right screen corner, I believe it's called the Overview button) to display "Recent Apps".

4. Tap "Clear All" (which just removes recent apps from the list)

5. Now Try calling into the Teams app from PSTN - my Android phone never rings, but gets a missed call indicator.

I'd take this info and get a support request started. Most folks on here won't be able to do anything to get this fixed :).

Didn't you just close the Teams app when you pressed Remove All? How would it ring if you closed it? Notifications are handled by Android natively which is why you would see the indication.

The "Clear all" doesn't actually close the app, it just removes it from the recent list displayed on the screen. It should still be running.

Nope, it closes it.,news-21281.html


Here’s how to kill applications running in the background.


3. Tap and hold on the application and swipe it to the right. This should kill the process from running and free up some RAM. If you want to close everything, press the "Clear All" button if its available to you.

Good catch, I'm on iOS so don't know better lol!

IOS doesn't have such an issue as the operating system provides a common extensible calling integration called CallKit. 

It may be a matter of semantics on Android, ("Closing vs. actually terminating a process"). I did a "Clear All" and in the running apps list Teams is still running, however, if I want to, from there I can do a "Force Stop". A lot of apps on Android behave this way.