Profile name not shown

I have Jami on Trisquel and on Android.

I made two of my family members install Jami on their iphone. Both of them see my username in their conversation list, they don’t see my profile name. It is the same when I make a call to them. This is a serious issue: they are so confused that they won’t answer a call.

Is there a way to ensure that the profile name is always shown?

On my side, I see the profile name for one of them, and only the username for the other, no idea why it is so.