any success with "Vinyl flat" and warped records

Not familiar with the method you are using. Way back in the day I had very mild success sandwiching a record between two heavy plates of glass. Then setting it outside in the sunshine. As I can no longer find the plates of glass I used, I suspect it may not have been as effective as I remember or just that I begun too make the move to CD's.

There is another thread here on this subject.Many claim great success.I returned mine because the bag did not work.My suspicion is yours doesn't either.Others document great results.I contacted the manufacturer who volunteered to exchange the bag.Suggest that avenue for you.

I no longer use my bag - I instead us my Breville Smart oven set for 150 deg. usually 45 minutes at a time.