Hello - most lenders notify you when the mortgage has been redeemed/paid off and then, usually within 2-3 weeks, they apply to us to remove the mortgage (legal charge) from the register
In this case the lender did that on 12th September and the register has been updated accordingly. No notification is issued to you as the registered owner.
The registered information is held by us electronically so there is nothing for you to physically hold to prove ownership and/or no mortgage in place -
see our blog article for guidance
The article also explains how if you want to you can download the registered information online or apply by pst at any time