It seems like I have the exact same issue as What could cause the Certificate Pending for the new custom domain?
My records follows your instructions and points to “morgendag-landing-page.onrender.com”
I bought this domain a couple of months ago but just started to set it up. I am using namecheap as my DNS provider.
I tried all the tools available on this forum yesterday but now I have to reach out to you render as per the other forums.