In Photoshop your png file is 2000px by 2000px it has a 1:1 Aspect ratio. In Photoshop your layered psd has a portrait aspect ratio. I think you must have distorted your image by using Image Size to force your image size to be a 1:1 aspect ratio 2000px by 2000px image. You should have first cropped your image to have a 1:1 aspect ratio. then resize the crop to 2000px by 2000px.
If you do not do a constraibed resize to preserve an imasge aspect ratio. the image will distort.