My SSL certificates got deleted

I made the jump over to GitLab as I was impressed by the GitLab Pages offering, especially regarding SSL certificates, however a week or 2 after setting them up for my website and subdomains, I just noticed my site is down (at the custom domain, not the *.gitlab.io mirror), with a certificate error saying its certificate only permits HTTPS on *.gitlab.io.

When I looked in the settings for the repo serving the site on GitLab, it showed no custom domain — it was 100% there and functioning a week or 2 ago though!

Does anyone have any idea how this happened? It took me a good while to manually set up each of the repos being served on GitLab Pages with these LetsEncrypt certificates, I’d rather not have to keep creating them if there’s a bug deleting them!

Any advice or insight would be appreciated, thanks!