Deleted Subdomains Still Active Pointing To A Different Subdomain

[PCZero]

One of my sites xxxx.net has several subdomains.

1.xxxx.net
2.xxxx.net
3.xxxx.net
4.xxxx.net
5.xxxx.net

I deleted two of the subdomains (2.xxxx.net and 3.xxxx.net). After deleting them, when I surf to those URLs, initially I got the standard "Warning: Potential Security Risk Ahead" page in FireFox. After clearing all of the cookies and site data in FF then rebooting the server, I no longer get that issue but now the deleted subdomains resolve to one of the other still active subdomains on that site. How do I fix this so that the deleted subdomains do not resolve at all?

 

[quietFinn]

One of my sites xxxx.net has several subdomains.

1.xxxx.net
2.xxxx.net
3.xxxx.net
4.xxxx.net
5.xxxx.net

I deleted two of the subdomains (2.xxxx.net and 3.xxxx.net). After deleting them, when I surf to those URLs, initially I got the standard "Warning: Potential Security Risk Ahead" page in FireFox. After clearing all of the cookies and site data in FF then rebooting the server, I no longer get that issue but now the deleted subdomains resolve to one of the other still active subdomains on that site. How do I fix this so that the deleted subdomains do not resolve at all?

You wait, until they expire in name servers.

 

[cPanelLauren]

Also, if any of them are pointing to a subdomain with a dedicated IP address, and the A record for the subdomain exists where DNS for it is hosted (i.e., remote dns/DNS hosted at registrar), you won't be able to change this behavior until the A record is removed.