Yes, there might be caching or other delays depending on how the zone is being edited (nsupdate results in fairly immediate changes, less sánh if some trang web front-end talks lớn a database that maybe eventually does something lớn update a zone), how zone transfers are done (the master DNS server might push changes, or the slaves could instead be configured lớn periodically poll that server for updates), and whether you are querying an authoritative DNS server or something else that might have cached the previous TXT record due lớn a previous query from your client, and thus is unaware of the changes the master server(s) might already know about.
Use nslookup or dig lớn query different servers (and also kiểm tra the SOA serial number, it should have bumped on a change, if not, you're looking at old data).
% dig +short @8.8.8.8 -t TXT google.com
"v=spf1 include:_spf.google.com ~all"
% dig +short @8.8.8.8 -t SOA google.com
ns2.google.com. dns-admin.google.com. 103585632 900 900 1800 60
The TTL of the TXT record might be an important thing lớn know; the full dig output should include that.