Best answer by Mohammed
These type's of numbers are considered premium numbers.
You'll need to enable Premium Messaging in the iD app/account.
You'll also need to ensure that your spend cap has some allowance available for this message to send. Most premium texts carry a charge to send. If your cap is set at £0.00, the message would not be allowed to go through.
Can you try enabling this & raising your spend cap to allow the message to send and try again?