Real-time voice or video communication between users on mobile devices or computers
It is no longer possible to send SMS messages from Skype/Teams. This feature was discontinued when Skype application was retired.
You can still make phone calls using your remaining credit from the Skype Dial Pad site on the Web:
https://calling.web.skype.com/
Just be sure to login to this site with exactly the same account as you have used with Skype.
In the case your credit has expired due to not being used within the last 180 days, this credit can be reactivated from this reactivation site: