This likely means you've been flagged as spam by the carriers. These blocks last about two hours before you will be able to start sending messages again. We have a temporary 2-hour cooldown status that shows up in your campaign when you've been marked as spam by carriers. This ban is NOT implemented by Sherpa, we put it there to try and keep everyone from missing prospects. Here's what you should do during that time:
Reconsider your messaging method. Most often, it's the high-frequency-messaging accounts that are being flagged as spam. We highly suggest leaving at least a few minutes between each batch to avoid sending too many messages too quickly. Five minutes should work, fifteen is great.
Go back to the drawing board with your templates - put yourself in the carriers' shoes and take out any language that might be commonly used in bulk/spam messages. Carriers are always becoming more strict with these spam filters, so use common, conversational language that would be hard for them to block and leave the specifics to the replies. Remember, though, to keep your intent clear in that first message so it doesn't appear as if you're selling anything. Refer to the language that has been known to be blocked here, but keep in mind this list is not exclusive and anything conveying a similar message may get flagged.