@SMJ56
Just to clear up a common misunderstanding, you are NOT the administrator on the PC; instead, you are an administrator class user with some admin rights. That is how Windows has been since Windows 7.
You said you had the PC cleaned up -- so what exactly was done to it?
Did it work OK after the cleaning?
Sorry, but we here can not help you with the PIN issue as we have no access to your PC.
To reset Admin passwords and PINs, you have to contact your regional HP Customer Support location directly for assistance.
https://support.hp.com/us-en/contact-hp?openCLC=true
I am a volunteer and I do not work for, nor represent, HP