There are many reasons that dlvr.it may not post some of your items. Often, this is related to problems with your feed or issues with Twitter or Facebook.
Additionally, if you have a premium dlvr.it Pro or Ultimate account plan and your credit card repeatedly fails, we'll pause your account and stop posting items on your behalf. We'll only pause your account after repeated credit card fails and multiple emails notifying you of the credit card issue.
To resume posting, just log into your dlvr.it account, go the Settings > Plans tab and update your billing information.