Mobile lighting is very limited right now.
My first guess would be to make sure your lights are marked static and that you have built lighting.
Most other forms of lighting won’t work, I think the only thing that mobile HDR allows you to do is emissive material but that is just off the top of my head, I have additional limitations since all of my lighting is done from dynamically placed rooms that are generated out of blueprints (so no static lighting)…
You can get more specific information on the official mobile lighting page: Rendering Features for Mobile Games in Unreal Engine | Unreal Engine 5.1 Documentation
I am hoping for some more magic in the coming builds to address some of the current limitations.