You changed a DNS record and some people see the new site while others see the old one, or nothing. DNS answers are cached for as long as the record's TTL says. Most changes are visible within an hour. Nameserver changes can take up to two days. If it has been longer, the change was probably made in the wrong place.
dig +short NS yourdomain.com. The record must be edited at that company. Editing DNS at your registrar does nothing if the nameservers point at Cloudflare or your host.dig +short A yourdomain.com @ns1.example.com using a name from step 1. If it shows the new address, the change is live and you are waiting on caches. If it shows the old one, the change did not save.dig A yourdomain.com shows a number in seconds next to the record. 86400 means caches can hold the old answer for a day. Lower it to 300 before your next move.yourdomain.com and www.yourdomain.com are separate records. People often fix one and forget the other.ipconfig /flushdns. On a Mac, sudo dscacheutil -flushcache. Or test on your phone with Wi-Fi off.Run dig +short A yourdomain.com @1.1.1.1 and dig +short A yourdomain.com @8.8.8.8. When both public resolvers show the new address, almost everyone does.
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