The title gives no right of way over the access to the property

The condition people breach without realising

Insurers of this kind of policy commonly require that its existence is not disclosed to anybody except lenders and potential purchasers. Telling the neighbour who owns the land that you have insured against him is exactly the disclosure the condition prohibits.

The same logic as every other indemnity: the cover depends on the risk staying dormant. Raising the subject with the person who could assert the right is what wakes it up.

Keep the policy somewhere you will find it, and hand it on when you sell.

The claim that may already exist

Where an access has been used openly and without interruption for a long period, a right can arise by prescription — a right established by long use rather than by grant — and it can be registered.

The evidence is the difficulty. It is usually assembled from statements of truth by the people who have used the access, which is why a statement from your seller is worth obtaining on completion even when a policy is being taken: it starts a chain of evidence that you can add to and hand on.

Whether a prescriptive claim is available here, and what period applies, is a question for your conveyancer on the facts. If you need a right rather than compensation, ask about the deed of easement route as well — it is more work and it is the only thing that produces the right itself.