Reg MSG-242"

Can you check if you are able to send messages via softphone.

Same issue I can find here

https://forums.developers.ringcentral.com/questions/9693/send-sms-in-production-msg-242-error.html

Also check the phone number you are sending the sms request in api

I am also facing the same issue: RCRequestId: 4b53b64e-9d3c-11ea-82f2-005056bbcdd9 and number +14705025057

can you validate this number registered correctly?

I am facing the same issue for "error code: MSG-242, Requested Feature is Not Available" while using the production environment. Whereas every thing works fine for sandbox environment. Below are the screenshots of my "Postman" environment setup and response of the "send SMS" endpoint.

Environment variables setup:

Response of "Send SMS endpoint":

I have created the App using JWT Auth.

Can you call this API and check if the number has the SmsSender feature. If it has the feature and still fails sending, then open a support ticket.