Poor Quality Bags/After Sales Service

I purchased a R1350 beige Pliage bag from a friendly Maria at Longchamp Waterfront. I was advised it can be cleaned by 'just wiping with liquid soap'. My previous Pliage bag made in Paris, purchased from this store, lasted years and I still use it. After 3 weeks of use, this bag was COVERED in black (mascara maybe?) marks that wouldn't wipe off easily. I also noticed the corners of the bags were cracked and broken open - after 3 week's use! I started googling and to my horror saw a lot of these 'luxurious French bags' are made in China! I quickly checked inside and saw, 'Made in China' and the quality of my bag is far inferior to the my last one. I went back to them & questioned the other assistant who assured me the bags WEREN'T made in China! I told her to check the label but she walked off. I left the bag and a note with Maria who advised I take up the state of my bag with management. I heard NOTHING for weeks. I went back and Maria said she was too embarrassed to call me, as they wouldn't do anything about it. I called Longchamp Paris who said I must email pics. Now V&A shop are saying I have to wash the bag before Paris will look at it? Shocking service, shocking quality bags!