Need help with Login page not working

I work in tech support and I cant use the auto type feature on the Zyxel login pages for the router… Each one is unique… I access the routers by (((https://158.124.xxx.xxx))))and sometimes http:// the initial login screen is same for all routers but the user name and password is different for each provider…
The username and password is different but the login screen is the same and I connect to them by entering ipaddress and sometimes ipaddress and port number… Im connected to a vpn that allows me to connect to these urls… I cant figure out how to use the auto type or auto fill feature… I can only get it to work on the address I been to previously…