Hi @BH531
Welcome to community!
Unfortunately, there isn't a way to remove an artist from your Top Artist list. Could you please share a screenshot of your top artist list with the artist you're not familiar with. You can include a picture here on community. This is best done through a web or mobile browser. You won't be able to share a picture through the email notification you may receive.
In the meantime, if you believe that there is an unauthorized user on your account. Steps can be taken to help protect your account.
To reset your password & remove devices:
From a web browser, go to pandora.com and log in to your account.
Then click your Profile in the top right corner of the page and select Settings.
Next to Account Info click on Edit to change your password. Enter your new password into the password field and Save.
You’ll be prompted to you enter your old password in order to be able to proceed with your request. Before selecting Submit, make sure to check the box to Log out of all other devices.
If you’ve signed into someone else’s computer, be sure to sign out of your Pandora account once you’re finished.
Keep in mind that it may take some time before the change will reflect on your other devices. Remember to sign out of your account once you're finished if you're not using a personal computer.
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