What is Blacklist number, and how to fix it?

My number is in the DND list? how and why?

Blacklists or Do Not Disturb (DND List) are filters put by the telecom company to protect their customers from spam and advertising.
The owner of the number asks his telecom company to be on this list, then he will not receive any messages unless from whitelisted transactional Sender IDs.
In Kuwait, Zain and Ooredoo implement DND Listing, STC/Viva & Virgin Mobile does not.

Only the owner of the number can ask to be removed from the list by calling his telecom company.

If messages are sent to a number in the DND list (Blacklisted number) from a promotional Sender ID, it will be blocked/filtered and not delivered. Also, credits will still be deducted and lost.

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