Additional Title Against Property for Parking

I'm in the process of conveyancing for a property, terraced house that was allocated 2 parking spaces in the original sale 28 years ago.

There's been several owners since, on the current plans the parking spaces, in the park area near the house, are not marked in blue.

During the searches a second title deed covering just the two parks spaces has been found unfortunately it is registered in the previous previous owner ie. The owner before the current (sellers).

Is this type of thing that can normally be resolved?

If so would contact be required with the older owner be needed to fix it?

Can anyone suggest how the second deed got registered without correctly linking to the main property dead?

This second dead appears to have been registered at the time when the 2010 owner was selling to the 2019 (current) owner but is still in the 2010s name.

Hi Michael - it reads as if there was a conveyancer/buyer error on the previous purchase. The transfer was of just the one title instead of two. It can happen, albeit rarely, but they'll need to get the old owner to now transfer it as appropriate.
If they think we erred and they applied for both titles then they can contact us to query the mistake. But in my mistake it's invariably the first scenario and they 'missed' the second title

Thanks for the response. It's appears its conveyancer error.

Does the old owner need to be involved in the process to rectify the transfer? 
What if they are not easily traceable?

​​Are there anything else that can be done in this situation?