Minor damage mainly repaired

This dress is in good condition apart from minor damage on the left strap. The button was coming loose due to a rip in the fabric and some of the elastic is showing. I've seen the button back on and secured it, but some elastic is still visible. I've pulled most of the elastic through the fabric to the inside of the dress, but it is just a temporary fix and I don't have the experience needed to mend something like this.