Thanks,
If your Normals texture sampler is set to ‘Normal’, you won’t need to do the *2+1 as they will be between -1 and 1 (also, would need to be done on the Blue too) - If you’re having to use another type of Texture Sampler that is correct though…
Also, rather than multiply them out, try the “Flatten Normal” node.
If that doesn’t fix it, one other thing to test is if your material is set to “Tangent Space” - if it isn’t that will also produce strange results…