I worked in sandbox 16503514555, and could send SMS . today it stopped and got error says 403 [OutboundSMS] permission required, I did not change anycode. is any way I can get permission back to send sms like before in sand box? it worked very well before.
https://platform.devtest.ringcentral.com/restapi/v1.0/account/~/extension/~/sms";
https://platform.devtest.ringcentral.com/restapi/v1.0/account/~/extension/~/sms";