Why is my level falling?

I’m new to UE4 and i was fine up until i moved my characters spawn point. Now my whole level just drops when i hit play. Any ideas or have i completely broken it?

Basically i start with pic1, and its fine. Then i play it and the ground moves away from the player start. the second pic is looking downward

What does this mean exactly ??? Makes no sense for me
But maybe this helps you:

https://docs.unrealengine.com/latest/INT/Gameplay/HowTo/SpawnAndDestroyActors/Blueprints/index.html

try to create an empty project or a new third person template or similar.

Please try to recreate the player start by deleating and recreating it: https://docs.unrealengine.com/latest/INT/Engine/Actors/PlayerStart/index.html
Also is your map ground created by using the landscape mode or is it a normal static mesh ?

Thanks, i will give that a go. If that fails ill try a new scene

landscape mode. it falling isn’t the spawn