Adobe software switches from one account to another

I am setting up a client's Lightroom CC, so I signed out of my account and logged into their account using their username and password on my computer.

Now Adobe keeps switching from account to account so that their email shows on my account and my name and email shows on their account. How do I separate the two accounts? It worked fine for the first few days.

Also, how do I get them to answer the phone? I've been on hold for 30 minutes.

Thank you.