This article is applicable only if your SMS carrier is one of these providers: Netsapiens, Ringlogix, UnitedCloud, Viirtue.
Issue
I can send outbound SMS messages from my Carrier Portal but I cannot send outbound SMS message from my SMS app in Teams.
Solution
Make sure the phone number is assigned the right SMS Carrier Profile. See the Phone Numbers article to learn more about managing phone numbers.
As a provider, make sure the SMS Carrier Profile works by clicking the "Verify Credentials" button. See SMS Carrier Configuration as a Reseller Admin for detailed instructions.