Vinted complaint: Item not as described

I purchased an item in good faith, it was described as new but without tags.
This item when arrived was clearly not new, it was used and damaged.
I contacted the seller within 10 minutes of the delivery and was advised that they were new but only worn once.
I told her they were clearly falsley advertised. They were worn and damaged and there was no way i could give this as the birthday present they were intended.
She then requested that they were retunred but told me if they arrive back to her damaged she will refuse them as it was obviously me that damaged them.
I told her i literally opened the box and i have proof that i sent her pictures of her damaged items within 10 minutes of the delivery driver ing delivery. She still holds her ground that i must pay for delivery to return them despite being damaged and not as described and that if they are returned damaged then she will refuse.
I asked for a partial refund to reflect the state and was refused.
I told her i would leave a review to reflect this and she has said that if i do she will leave a review on mine as a seller to say that i was a scammer to punish me.
I have contacted customer services over the period of a a few days to simply receive generic emails back and for them to refuse to help.
I asked for this to be escalated as a formal complaint but was refused. I asked for an investigation into the seller and was refused, i asked for a refund and was refused.
All they say is send the item back by 21st July or they will release the money.
I have told them why should i have to pay to send the item back, especially when the seller has stated she will refuse the return.
Again i get no answer. I have also sent an email to the CEO with no reply so this is a last resort