When there are too many SMS/Email being sent to customers at the same time, the system will automatically put these commands into the queue, the SMS/Email will be sent case by case.
This explains why your customers do not receive messages instantly when you choose the Start now button for delivery time. Typically, this process will take probably 10 minutes or longer to complete depends on the number of recipients.
After the said period, if you are still failed to perform this function or your customers are not able to get your SMS/Email, please reach us out immediately to have further assistance.
The credit is important to perform the SMS sending. Please make sure your balance must be greater than $0.5 to perform this feature.
If you need more support, please let us know via our live chat or email us at firstname.lastname@example.org