How to overcome the problem with dns?

Question

Domain Name System

Good afternoon, in general, I encountered an incomprehensible problem for me, if you can please explain what's wrong.
The situation is as follows, recently my domain was tied to vps1, where it was on its own ns servers. After purchasing vps2 (current) I changed server ns (to domain registrar server ns) and redirected all requests to ip vps2 (A-records for mail, @, * and mx respectively).
As a result, I have:
1. From the site 2ip.ru, when checking the main domain, the current vps2 address is pinged.
2. With the command line of my home computer, for the main domain, the old vps1 address is pinged, and for new subdomains, the new address is vps2.
3. In the terminal of the current vps2 for subdomains and the main domain, the old ip (vps1) is resolved.
4. Domain mail from the vps2 subdomain leaves the ip vps2 server.
In general, I am a little confused and do not fully understand whether I did something wrong, or whether dns are being updated fanwise and some have not had time to update.
Thank you.

Answer 1

DNS records are updated according to the TTL record, if you say it was set for a day, then you need to wait a day for a full update