Question on Wifi Calling on Samsung S9

I recently bought a S9 because I know it supports WiFi calling/texting(I'm with Telus). I work offshore on an oil rig with no cell service, so Wifi calling/texting would be really convenient for me. Only thing, I'm out here now and it is not working on my phone.

When I was on land, I had it working on a couple WiFi networks, but not all. So I assumed the wireless network had to setup for it. I have a co-worker with a iPhone 8 and is with Telus, and he can use WiFi calling on his phone.

Any thoughts on what my issue could be?

Thanks

I have issue with a out of service Samsung J3 Prime (J327t1) and have Dingtone installed.
For some WiFi spots like the local library DT won't connect while other WiFi networks it does.
Do you have to login to the network like what I have to do at the library?
Maybe the iPhone app works a little different. IDK?

I connect to an open network, no login in required.