Cannot send direct messages to host. "[host user name] is restricted from receiving direct messages"

[astraleo]

  I cannot send direct messages to the meeting host.  I am getting an 'error' message when trying to send a (private) "direct message" to the meeting host. It disallows sending my message and says, "[host user name] is restricted from receiving direct messages".   But the host has not disabled anything.

  I have been using Zoom since March 2020 as a host, cohost, and participant.  I have co/hosted hundreds of meetings since then, so I know my way around most of the more common settings, including the account holder universal settings.  I have used Zoom on various iterations of Windows, Mac, Chrome, iPhone, iPad, Android tablets, etc.  The problem is currently being experienced on an iPhone 13ProMax. 

  I am presently in a meeting as a participant with 10-15 people and a single host on an enterprise account for a college. (The host is in TX, and the participants are in CA.)  On more than one recent occasion, I have been receiving this 'error' message when trying to send a direct message to the host.  I can send a direct message to 'Everyone', and the host can send a direct message to me. But I cannot send one to the host.  Other participants, including me simultaneously joined from another device, are able to send direct messages to the host. Direct messages between participants have been disabled. (I.e., direct messages can only be sent to the host and to 'everyone', but not to each other.)

  Neither the host nor I know anything about this 'error' and cannot see how to disable/enable this.  The host has not intentionally blocked anyone.  In fact, the host has not made any changes to the chat settings. The host is in the main room with all participants (has not joined a breakout room).

  Something else:  I was able to send a test direct message to "Everyone".  After that, I was also able to send a direct message to the host.  Neither of us knows why I am suddenly able to send a message to the host.  Coincidence?

  We would very much appreciate any information regarding how to re-enable (or even how to enable/disable) direct messages between a participant and a host.  Is this a host thing, a user thing, a universal thing?  Is there a setting for this? Or is this a mysterious bug?  Thank you in advance.