Custom server template stuck at "default"

So like i said in the title i made custom server template by selecting “Create an empty template”. Now when i want to change something on that custom template it will go back to “default” or better to say if i use that custom template i will get same settings i have in default one.
Whatever i try to change and click save once i go back to see if everything was saved i found that new template just changed everything back how it is on default template. I even try to make new server and in fact Virtualmin made it by using default template.

Is this a bug or i’m missing something?

Just to make one example:
In Bind on default i have set nameservers ns1.xxx.com. Now when i create new template and go to Bind it will be grayed out with selected option “From default settings”. If i change that to "Records below … " what will allow me to change settings in Bind, and lets say i put nameserver ns1.zzz.com. Once i click save and go back to check Bind settings will be grayed out and “From default settings” is selected again. If i try to use custom template to make new server it will use Bind settings from default and not one i saved in custom template.

Centos7, Virtualmin/Webmin.

Really no one encounter this problem?