Has the bag been previously authenticated?
I would try placing heavy items but not too heavy (i.e. lots of papers or something like that) in the bag and then hang the bag from a door knob. That’s just me personally — I don’t baby my bags though.
If that didn’t work, I would take it into H and see what their craftsman can do.
Good luck!
You could try shaping tissue paper or a small bed roll to insert into the handle opening to reform them. I’ve done this with an old favorite that my DD used and abused. Give it time as it does work.