Our forum went down on October 16, 2020 because SSL certificate expired. We are using automatic letsencrypt SSL certificate renewal script. Debugging the issue using cPanel's Manage SSL sites failed:

A fatal error or timeout occurred while processing this directive. [show] [close]

Template::Exception:
[TYPE]=[undef]
[INFO]=[SSL::installed_hosts(HASH(0x2b72530)) failed: Unrecognized vhost: “forum.webseodesigners.com” at /usr/local/cpanel/Cpanel/Config/WebVhosts.pm line 391.

]
[TEXT]=[]
at cpanel.pl line 1121.
cpanel::cpanel::cptt_exectag("/usr/local/cpanel/base/frontend/paper_lantern/ssl/install.htm"..., 1) called at cpanel.pl line 4489
cpanel::cpanel::run_standard_mode() called at cpanel.pl line 925
cpanel::cpanel::script("cpanel::cpanel", "./frontend/paper_lantern/ssl/install.html.tt") called at cpanel.pl line 323

Without root access there was nothing anyone can do to fix such issues so I had to contact GoDaddy support. They created a ticket and about half a day later the issue was fixed. I was able to access Manage SSL sites and ready to add back the forum's addon domain forum.webseodesigners.com. Surprisingly, that did not work anymore either:

(XID 6f22nc) A DNS entry for “forum.webseodesigners.com” already exists. You must remove this DNS entry from this server or all servers in the DNS cluster to proceed.

To get the second issue fixed, support opened another ticket and they did some kind of hack to get the subdomain back into cPanel configurations. The issue could be related to an old hack GoDaddy has made to prevent clients moving domains between different GoDaddy hosting accounts. Failed subdomain was back in cPanel 3 hours later. I managed to check the certificate and it was indeed valid until Jan 15, 2021 7:54:32 AM, but GoDaddy kept serving magically the old, expired certificate which was nowhere to be found in the system. I contacted the support for the 3rd time and they promised that the issue will be fixed in 2-3 hours.
The next day the certificate was still broken. During my final chat with GoDaddy, support was copy-pasting to me some very basic instructions how to use SSL certificates and marketed their crappy and useless security products, and expensive certificates as a solution to my problem. Then the support person claimed that everything is working and confessed that their admin/advanced support team had refused to open a ticket to solve the issue before he hang up.

There is nothing anyone could do to fix such issues without root access. The rest of the websites and SSL certificates on the same hosting account had no issues and renewing certificates worked as well. That made me wonder had GoDaddy deliberately sabotaged the certificate renewal to get rid of the this forum. Dreamhost pulled a similar stunt 1.5 years ago forcing us to move the forum away. Another, more likely explanation, is their technical incompetence coupled with laziness.
I spent altogether 8 hours 3 minutes chatting with the support and this forum was inaccessible for 2 days. The issue was finally solved in 32 minutes and 3 hours of waiting for the DNS to propagate all over the world by moving the forum to another hosting. If you have such technical issues on GoDaddy that you can not solve by yourself, it is faster and cheaper to move your hosting away from GoDaddy than trying to get their issues fixed.