Can I get a refund if my child sends a text message with a secondary number?

I can't. If the child sends a message with a secondary number, the fee is non-refundable. As long as it is manually buckled, it cannot be returned. If you automatically deduct money without any operation, you can get it back. This can be found in the background of the operator. Even if the child is not sensible enough, playing with the mobile phone is wrong, which is equivalent to your own recognition.