Help! How do I set up health insurance through ADP?

I'm currently eligible to set up health insurance through my employer through ADP. I went to the ADP portal, https://portal.adp.com,/ at work earlier this week, logged in, and saw the insurance options. That's the page I want to get to.

Now I'm trying to access it from home, but when I enter that exact same URL, it doesn't accept my user name and password. It will accept a different user name and password, and then it takes me to a page where I can view all my pay stubs, but that's it.

How do I get to the page where I can change my health insurance? I don't understand why I'm going to the exact same website and it won't let me in. ADP is useless; they tell me to contact my employer directly, and they're not available on the weekend.

Thank you!