After digging around, I discovered the problem was that Google blocked Hetzner’s IP addresses. Other people have faced similar issues, and their solution was to disable IPv6 and then reserve the floating IPv4. Another solution is to get a new IPv4. In my case, I host N8N to another server. After migrating to AWS, everything works as intended. I’ll put it here as a note if someone also faces the same problem when deploying N8N in Hetzner with/without Coolify.
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