Vinted complaint: Item damaged in transit

Posted an item in a mail bag to the buyer and some how the item was damaged in transit! (The parcel looks as if it has been chewed) contacted Vinted who told me they were going to contact the currier to investigate the issue however, Vinted did not do this and instead made a decision themself based on the photos provided. They claim the package was not packaged properly even though it was in a mailing bag and their packaging guidelines state a plastic reusable bag is fine!

Vinted have cancelled the order and refunded the buyer which they should have done however, they are refusing to compensate me and I am now out of pocket and do not have an item to resell!

All my reviews are 5 star and positive, I always use mailing bags to send my items and have never had this issue before!

I am very disappointed in Vinted for not doing their job properly and contacting the currier to investigate this, further more I have a child to feed and do not sell on Vinted for the fun of it, I actually need the money!