I have registered and delegated a domain name
thetabox.ru with the domain name registrar, which allows me to edit a zone file for my domain. I have also set up a VPS with a hosting company, which allowed me to manage DNS records for my server zone.
Originally zone records matched each other. Since then I changed the hosting company and changed some DNS records with the domain name registrar. However, even after SOA TTL expired, DNS queries to public DNS servers are getting records from the VPS hosting company's zone file, which I am not using (for example, https://www.nic.ru/whois/?domain=thetabox.ru returns my hosting company
ns1.ihc.ru as a nameserver, not
ns1.r01.ru as it should be according to the domain name registrar records).
What determines zone delegation, if both zones claim being the SOA for the domain? Is TTL greater than I expected?