If you use your SenderID to send critical notifications and activation OTP/codes and need them to be delivered to everyone even Blacklisted/DND numbers, then you must apply for whitelisting your Sender ID.
Prepare a request with your company letterhead and send it to us with company license and civil id, we will take care of the rest. (Example Letter)
+ Do you have contracts/monthly sending limits?
+ I want to advertise my business/product, do you provide lists?
+ Can I Send Link (or URL) in SMS messages?