Altice Optimum DVR playback error: VID-218: does NOT playback!

It happens from time to time. Instead of playing a recording Altice Optimum displays this error: VID-218. And shows an OK button to click. Obviously, it's not OK.

It impacts a few recordings but not all. I have two set top boxes, those mini Altice boxes. The secondary box seems more vulnerable.

Tonight neither box will play any recordings.

I searched on the error code VID-218 but could not find an answer. I rebooted both boxes. Then I logged into the Altice Optimum website and sought support. I wound up in one of those useless chat sessions, which ended this way:

VID-218
You - 7:51 PM
Let me get one of our live experts to help you. I'll just need to grab some quick info from you, then I can get you to an agent.
Can I have your name?
Allie - 7:51 PM
Ken
You - 7:51 PM
And your 10-digit phone number?
Allie - 7:51 PM
999-999-9999
You - 7:52 PM
I will transfer you over now to our Technical Department so we can get the team to help you. Thank you for your patience! One moment...
Allie - 7:52 PM

(After waiting five minutes I decided to provide information, hoping that the tech person would be able to read it and that would make the conversation shorter and more productive.) I typed:

VID-218
No DVR playback.
You - 7:58 PM
I can replay DVR recording on my Android phone but not on my TV using your Altice mini box.
Waiting 15 minutes. Call me: 999-999-9999. Bye.
You

_________________

What the heck?