Texture being stretched into nothingness

[IamACoolGuy_1230 (Scorch)]

So I am trying to create a planet out of multiple meshes, so that I can make them look more detailed (Roblox limits triangles to 10k per mesh). However, when I uploaded the texture for a part of the planet, it appears to be stretching all the way around a non existant circle, which is very odd.

Here is an image of the issue:

And this is the origional texture:

As you can see, the whole texture is not being shown on the part.

I am quite new to blender and UV mapping and all of that stuff, so any help is greatly appreciated!

(Side note: the texture is perfectly fine on a flat part):

[BilonGamer (Bilon)]

Does the texture look right in Blender?

[IamACoolGuy_1230 (Scorch)]

I just realised that the UV map was still of the entire planet texture, not just the small section of the planet. I changed the material to that section and UV mapped accordingly, and now it works completely fine!