@Elena2
@Elena2
you have the Quebec $43 Canada US plan?
Critical part to US roaming depends on T-Mobile coverage and whether you can connect to T-Mobile network or not
If the phone is not connecting to T-Mobile, change the Network Connection from Automatic to Manual and select T-Mobile
If your issue is with data, make sure your Roaming Mobile data is enabled and your have disabled your mobile data limter
If your issue is with voice, make sure VoLTE is enabled on the device setting. And if it does not work, try to change the Preferred Network Type or Network Mode to 2G and see if the calls goes through
Also, you can download VoIP app TextNow as a workaround to make calls and text if you have Wifi or if your roaming has data component and data is working
