Deleting User 2010 Macbook Pro

Hello,

I've posted this before but I am reposting with a screenshot! :

I have a 2010 Macbook Pro, I am trying to delete a user from my computer.

I go to system preferences, user and groups, I see the profile I want to delete.

I sign into my admin account by pressing on the lock.

It is not giving me the option to press the "-" sign to delete the profile I am looking to delete. Right clicking for advanced options is also not giving me any options. My only option is the "+" but I don't want to add any accounts!

Can you tell me step by step how to remove the user?

Thank you!