This issue is very similar to (if not exactly the same as) There was a problem loading this website, but unfortunately it seems to be impossible to solve this without help from Cloudflare.
Situation is as follows:
- Client used to have a Shopify webshop, configured according to the “Connecting a third-party subdomain to Shopify” instructions as provided by Shopify. So just a regular CNAME, nothing else. Hostname: shop.[domain-name] - can’t post the domain name here unfortunately.
- Client decides to leave Shopify and switches to an alternative, “traditional” (so no SaaS) solution. So simply a matter of removing the Shopify record, you’d say.
- We replace the CNAME record in Cloudflare with a regular A record with proxy enabled, also named shop.[domain-name].
- For some reason, we keep seeing the Shopify “There was a problem loading this website” error message even though the domain name has been unlinked from Shopify and there are no traces of Shopify left in the DNS. If we disable the proxy then we see the intended page (but with an SSL error because we use the origin SSL feature), if we enable the proxy then Shopify pops up again.
So far we tried the usual waiting (6 hours by the time or writing), adding and removing the record multipel times, pulling hairs etc. In case Cloudflare Support is willing to lend a hand: ticket to Partner Support was submitted but immediately close, filed under 2516853.