If your title deeds have been misplaced or lost, your first port of call is the solicitor and mortgage lender that helped with your property purchase.
If you still cannot locate them, you will need to apply to the Land Registry for a First Registration. This involves completing forms, providing the Land Registry with as much information as possible, and supporting the registration request with a history of its ownership. This can include death certificates, probate forms, conveyancing letters, and mortgage statements.