Garden access situation

[Daman172]

We brought our house in November 2023 it's a semi detached property with our property adjoining the house on our right. The problem we are having at the moment is gaining access to our back garden. The gate leading to our back garden is on our neighbours land to our left. This is now causing a problem because our neighbour is is being very awkward about us going on his land to use the gate to access our back garden he says he wants to do this and that to his house/garden we know this isn't true but he says we won't be able to use the gate very soon. I have been doing a little research and wonder if there a way we can dispute the boundary line on the deed because it does not make any sense why our gate would be on his land? Would we be able to use the Access to neighbouring land act 1992? Any help or advice on how to claim the little bit of land from him where on gate is would be truly appreciated.

[PallasAthena]

What do your title deeds at the Land Registry say about any right of way you have across the neighbour's land to reach your garden? Rights of way across neighbours' land are quite common in cases like this.