I'm glad that you were able to resolve your issue and thank you for posting your solution so that others experiencing the same thing can easily reference this! Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others ", I'll repost your solution in case you'd like to accept the answer .
Issue:
- Customer is unable to receive the sms using azure communication service.
Solution:
- Upon investigating further, @Imran QADIR BAKSH found that this Most probably the issue will be related to regulations https://learn.microsoft.com/en-us/azure/communication-services/concepts/sms/sms-faq#toll-free-verification
If I missed anything please let me know and I'd be happy to add it to my answer, or feel free to comment below with any additional information.
I hope this helps!
If you have any other questions, please let me know. Thank you again for your time and patience throughout this issue.