Unable to make calls in US with AT&T

[Frustrated21]

I've been going to US several times now and thankfully I got a Canada/US plan which helps however every time I'm there it connects to AT&T so I'm able to send/recv SMS and Data is working as well but unable to make/receive calls.

I'm also a bit techy, so changed to manual network selection and I chose Verizon and everything is working fine however after few minutes it changes to AT&T again, really frustrating ... Does anything know a solution about this ????

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[LordDrakkon]

Is tiaming enabled on your device? The default roaming partner is AT&T. Only in places where AT&T does not have service, will a connection to Verizon or T-Mobile be permitted.

What device and model are you using? If you are using an older device that does not support a compatible version of VoLTE, you will not be able to make or receive calls in the US. Have you tried contacting Support by calling 611 from your device while connected to WiFi Calling to have them refresh your connection to the AT&T network?