I encounted this issue as well (posted about it here: Self-Signed Certificate after 2.3.3 Upgrade - #3 by shoaibkk) and did the manual SSL renew to fix it. Looks like on 03/18/2023 these certs renewed again (very fast since they’re good for 90 days) and it’s interesting. Some sites got the self-signed certificate, and some got valid let’s encrypt certificates.
Can you point me to the logs for this? I’d love to attach them to hopefully help get to the bottom of this.
EDIT: I just edited the ~/.acme.sh/account.conf file and enabled logging. I’ll need to set up log rotation, but hopefully next time this happens I’ll have some actionable logs. The acme.sh script in the directory is v3.0.6 which seems to be the current one on Github. Going into the SSL menu, selecting the site, and clicking Issue SSL resolves the issue.
Interestingly, like 3 of the 9 sites I manage had the renewal complete successfully. The rest dropped back to self signed, and not because they were due for renewal. I literally went through this around 3 weeks ago. Very strange.