Lululemon like a cloud longline bra-purple

Lululemon like a cloud ribbed longline bra in a really pretty purple color. I am not sure of the size as there are no tags I could find, but the measurements are shown in the photos. Someone gave it to me and I was told it was a size 6, but it seems too tight to be a 6. I’m guessing it’s a 4, but not positive. There is a small bleach stain on one of the straps (see photo), but it is otherwise in great condition