My domain is showing the wrong site

Work through these in order — the first two explain most cases.

1. Your computer is holding an old answer

Try the domain on a phone with Wi-Fi off. If the phone shows the right site, the DNS change is working and your own machine has cached the old one. On Windows, ipconfig /flushdns; on macOS, sudo killall -HUP mDNSResponder.

2. There is more than one record for the name

Two A records for www means visitors get one or the other at random, which looks exactly like an intermittent fault. Check Domains → your domain → DNS and remove the one pointing at the old host.

3. The nameservers still point at your old provider

If the domain's NS records name your previous host, they are answering, and nothing you change here is being read. The DNS panel here shows a warning when it can see this.

4. example.com and www.example.com are configured differently

They are two separate names and need two records. A site that works on one and not the other is nearly always this.

5. The old host is still serving a redirect

Some hosts leave a redirect in place after you leave. If the domain resolves to our address but you land somewhere else, it is a redirect rather than DNS — check with curl -I https://example.com and look at the Location header.