HTTPSを使用したwwwから非wwwへのリダイレクト

[merefield (Robert)]

Yep that’s your first and main problem, see:

Set up Let’s Encrypt with multiple domains / redirects

This is to address the problem where you get certificate errors with any redirects or CNAME DNS entries which point to your actual installed Discourse (sub)domain. If you do not have https configured already (you do if you have done a standard install recently) see Setting up Let’s Encrypt as your first step. There are two patterns that need to be replaced, one ending in --keylength, and another ending in --fullchainpath (in the actual file, your original domain is before each of these switche…