Two title deeds

Hello
I own a property which I purchased for my mother to live in with the man she was married to.
Title deed was updated to reflect this.
Both have now passed away it now transpires there are two title deeds.
One that I have always had freehold.
Then a different numbered one leasehold is on land registry. This states that they pay a peppercorn rent. But it has them down as the proprietors.
Surely they should not be named proprietors. Has a mistake been made somewhere along the line. Has somebody updated things wrong.
Very worrying as I am now needing to sell the property.
Thank you

Hello Tommy - I doubt if there has been a registration mistake as you have two separate tenures, freehold and leasehold. The leasehold would only be closed (determined) if an application was made to do so.
If they are now both deceased then you will need to transfer the leasehold title as the executor and into your name as the beneficiary. And if the lease is to be closed also apply to then merge it into it's freehold.
Our online guidance explains how to update the leasehold title re the change of ownership 
Section 3 of our PG 26 explains how to include a request to merge the two tenures under the same application