Incoming US calls failing while roaming in Brazil – ported 4 lines from AT&T recently
A couple of months ago, we transferred 4 family lines from AT&T to US Mobile. The porting process was smooth, but we’re now running into a major international roaming issue.
When we were with AT&T, international travel (including to Brazil) was always seamless, which was a huge factor for us when choosing a carrier. My wife traveled to Brazil this week, and since arriving, she has been unable to receive incoming calls from the US consistently.
She reached out to US Mobile tech support, and they suggested manually switching between different local networks in Brazil (Vivo, Claro, TIM, etc.). She tried this, but the issue persists. With AT&T, connecting to local partner networks worked without any hitch, so we're trying to figure out why this is happening with US Mobile
I am heading to Brazil later this week to join her, and I urgently need reliable call reception for my US-based business while I'm away.
A few questions for the community / US Mobile team:
Has anyone experienced similar issues receiving US calls while roaming in South America?
Are there specific backend settings, provisioning updates, or APN configurations needed for smooth incoming voice calls in Brazil?
Which underlying network (Warp / Dark Star / Light Speed) handles international voice roaming best in this region?
Any advice, fixes, or help from the US Mobile mods/support team here would be greatly appreciated! Thanks in advance!