Did you check in the BIOS to see if there is an option to clear the TPM? I see you turned the TPM off, so I'm assuming that you are now signing in with a password. If you are using a password and don't use BitLocker it should be safe to turn the TPM on and then clear it. After that you should be able to login and setup a new pin number. Don't forget to have a backup image before you try anything. It's also possible that you have a defective motherboard.
Actually there is a way to clear TPM from within windows and MS suggests it be the first method to use when one wants to reset TPM. Troubleshoot the TPM (Windows) - Windows security
Doing it in Windows is just another way to access the Bios to clear the TPM. I look at it as one way is manual the other way is automatic.
Conspiracy theory alert!!
MS knew TPM would be a can of worms. MS knew the bios was foreign to a lot of people so they gave an Automatic way of clearing it. 
