Hello,
What is the domain name? Are you also trying to change your MX records?
It typically takes up to 48 hours for the internet to see a change in your DNS servers.
DNS resolvers that picked up the new servers also might not get the information about the change back to the old DNS servers for 48 hours.
This should not matter as long as your zone file is the same on both servers, but it sounds like your zone file is different between the servers.
The zone file is all of your A, MX, CNAME records for example
IANA — Example domains and mail.example.com.
The best thing to do is have the zone file set correctly on both sets of DNS servers BEFORE you make any DNS servers changes, and drop the TTL's the records in your zone files and make those changes either a couple days before or after the DNS server changes to reduce the chances of there being complications.
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