iMessages that are delivered intermittently marked "not delivered" on Mac but not iPhone
when sending messages using iMessage on my Mac, I am intermittently seeing a red exclamation point that says "not delivered" but the messages are being delivered as reported by recipients and shown on my iPhone. This issue started in the last few days and I have not made any changes in the past few months.
MacBook Pro (Retina, 13-inch, Late 2013), macOS High Sierra (10.13.6)