This incident has been resolved.

Facebook API is now back to normal and we are monitoring the results.

Facebook APIs remain unreliable. The issues have been reported to Facebook Messenger team. You can track progress here: https://developers.facebook.com/support/bugs/319230892086048/, https://developers.facebook.com/support/bugs/353471685302112/ and https://developers.facebook.com/support/bugs/1285256981629769/

Facebook APIs that power connecting and disconnecting pages in the Dashboard are affected too so this functionality is currently unavailable as well.

Our systems detected increased number of errors from Facebook Messenger Send API which affects bots' responsiveness and broadcast delivery. We're monitoring the situation and we'll let you know as soon as there are any updates.