If you are unable to send messages, chances are that your account has been placed on hold.
This typically happens if you have exceeded the sending limits of our API or if there was a declined or failed transaction while trying to renew your subscription.
Thankfully, you are still able to access your account when it is placed on hold. Furthermore, your data, including messages you have created, will remain in place.
Please contact us if your account is on hold so that we can help unfreeze it.