Hello and welcome to the forum.
#1.) The first thing you need to do, is to make absolutely sure, without any doubt, that the account you intend to use going forward, is a member of the local administrators group and not a standard user
AND
#2.) In the interest of keeping some continuity and just to be on the safe side, you might be better off just disabling the other account that you do not wish to use or see.
Right click the start button and choose Command Prompt (Admin) from the context menu and in the command prompt window type
net user <UserName> /active:no
EXAMPLE: IF you have a user named <JohnSmith> it would look like this
net user JohnSmith /active:no
hit enter
IF there is a space in the user name such as <John Smith> then that user name has to be surrounded by Quotation Marks ....
net user "John Smith" /active:no
hit enter
#3.) It might be a good idea before doing any of the above to check and confirm your users to make sure you are clear as to their presence on the machine.
In the same elevated command prompt just type
net user
hit enter
That should show you all the users that Windows is aware of on the computer.