What if we try to change the avatar photo and it won't take?

It may be that the photo is too large. Usually mylot will tell you if the photo is too large but sometime not. I would try it again and if it doesn't work then I would change the size of the picture. Good luck and welcome to mylot!

I cant Change mine for some reason

I have not had this problem, so I can only guess at what the cause might be. It could be that the image is too large, although I am not sure what size restriction exists in this case. It could also be the file format that is not compatable. If the image was created in an image editing program and saved as the default type, then maybe the site cannot read the file. I would suggest sticking to jpeg or gif for any images.