According to the most recent updates from TRAI, in compliance with the DLT set-up to avoid unsolicited messages being sent out, there is an additional check that will happen at the DLT platform level, while scrubbing the preferences of the end subscriber.

So, in case the end subscriber or recipient has explicitly selected their preference as not wanting to receive promotional messages or other such settings, then the status of that message sent to that number, (which would not be delivered) will have the status as "PREFERENCE NOT MATCHED"

To read more about the preference selection and options available to customers, click here.