I've been receiving a few of these lately, not sure if I should be concerned or not. The full message is:
The remote collector has not acknowledged 2284010 bytes of data sent by the local agent over the secure connection. This may indicate high latency or an issue with the remote collector, it's recommended that you ensure that data sent from this host is present in the web reports. The agent will now throttle data sent to the collector until the collector acknowledges receipt of sent data.
Please let me know if there is more data I can provide to assist in assisting,