Proton has a nice tool for helping one configure DNS records to migrate an email domain to the Proton servers. However, the tool completely hides any details when something is not working correctly which makes it difficult to diagnose and resolve. If one uses the Refresh Status in the Domain names page, and some items show as being incorrect, one should be able to get the following details of what went wrong:
1. The IP of the DNS server that was queried
2. The response that was received
3. The response that was expected
Without these details it is difficult to know whether the query simply got a stale, cached answer, or was talking to the wrong DNS server or the root server is incorrectly configured.