TNB can change name and start new account as long as you are the legal new owner.
The previous debt will always be accounted to the previous account bearer name be it ex owner or tenant name.

Maintenance fees, cukai taksiran, etc will always tied down to the unit number.
Need to pay/settle.

Refer the POS. most banks cover this up until the auction date. but is pay first and claim back process.

It is not waiver. But outstanding will be under the defaulter name. TNB will chase the defaulter.
For TNB, outstanding is not tied to the unit address but tied to the account holder.
New owner no not need to pay this.

Just apply and open a new account.

That is also why TNB encourages those renting out units to register TNB account under the tenant name.