Hopefully someone will be able to shed some light on the following.

I am on Skinny prepay and use wifi calling. I have an Android phone (Pixel 8 Pro).

My employer uses the Spark network. 

On three occasions now, two team leaders from work have tried to call me on my mobile using their respective work supplied mobile (Iphones).

Each time my phone will ring maybe two rings then stop and it will show a missed call.

The callers phone will have the normal ringing tone and then after about two rings will disconnect and their phone will display the message "call cancelled".

These two people have called me in the past without issue. This issue has only arisen since April this year. TXT messages go through to and from without issue.

I have tried calling my phone with one on the 2degrees network and it goes through fine without any issues.

To be honest I'm not too fussed about it as when they call it's usually because they want me to come into work!

Just curious as to what's going on.

Edit: If I call them the issue does not occur.