Check what a domain's DNS actually says right now — A, AAAA, CNAME, MX, TXT, NS, and SOA records, pulled live from a public resolver with their TTLs.
What do the record types mean? A points a name to an IPv4 address and AAAA to IPv6. CNAME points a name at another name. MX says which servers accept email for the domain, TXT holds text notes (often ownership proofs and email anti-spoofing rules), NS lists the domain's nameservers, and SOA is the zone's admin record.
Why do my DNS changes not show up yet? DNS answers are cached around the internet for the length of each record's TTL (shown above, in seconds). A change made a minute ago may keep serving the old answer until those caches expire — that wait is propagation, and no tool can skip it.