How Would I Fix These?

[Linux for blind general discussion]

Hi All: Well, this morning, as usual I ran an update-and-upgrade. Certainly 
alot of packages coming-and-going. This machine has been up 91 days, still in 
Debian SID kernel 5.18, although the updates are now in 6.0. Anyway an hour 
afterward, I began seeing `alot of these mail errors. Getting clobered with 
them. I receive mail through an imap through fastmail.
From: Mail Delivery System <Mailer-Daemon at chime.lan>
Subject: Message frozen
Message 1olB28-00CLcA-08 has been frozen (delivery error message).
The sender is <>.
The following address(es) have yet to be delivered:

bounce-65022_HTML-646632331-83081-514007347-393633 at bounce.g.s11.pdmailservice.com: 
Mailing to remote domains not supported
Back again live, I even sent a group of these to spam, but I guess since these 
are not real messages, it may not do any good. exim was 1 of the packages 
updated. I am probably receiving 6 of these every 5minutes. I must go in 
alpine-and-run an aggregate for frozen. Anyway, has this ever happen to any of 
you-and-how did you fix it? Thanks so much in advance.
Chime