Can anyone help me with this error?

Your textures are too high resolution. You're only allowed to use a total texture "size" of 5,000,000 pixels and you're currently using 15,000,000 pixels.

You need to either use lower resolution textures or reuse textures by tiling them when appropriate.

For future reference, such common LFS exitor errors are described in the LFS manual: https://en.lfsmanual.net/wiki/LFS_Editor_FAQ#Total_png_texture_area_limit_of_5_megapixels_exceeded_by_X_megapixels