Two months ago I registered bunch of expired domains and set new nameservers to them just like I've done before. Never had any issues.
For some reason the DNS propagation never finished with these domains. When I use any DNS propagation checker, they show that some of the servers are pointing to the correct IP, but many are still pointing to the old ones. And they keep switching between the new and old ones.
One example is domain.ax. If you go to whois.ax (the official .ax registry site) to check the domain, it tells that the nameservers are correct, hostgator.com ones. But when checking with tools like intodns.com, they find more nameservers. In this case parkingcrew.net nameservers, which were set by the previous owner of the domain. And again, DNS propagation checkers find up to four different IPs, at the moment correct should be the one ending .188.
Any suggestions what could be wrong here? My knowledge about this stuff is very limited.