Vinted complaint: Not giving me a refund and refusing to answer why they marked my order as completed on my behalf

In late August I ordered two items via Vinted. They arrived after my departure abroad. I assumed (like it alwasy happens), when an order is never picked up, it gets send back to the seller and I can rebuy and get a refund.

Upon my return to the UK, I looked at my app and found out that both my orders were marked as Completed. I did not do such thing obviously. When I tried to ask them why they did taht and that I have not gotten my parcels, all they kept saying is I am sorry you do not find our solution satisfying but you missed the 48 hour window you have after marking the orders complteded to dispute. That is NOT A SOLUTION. I have asked repetedly WHY they marked my order completed on my behalf and noone ever answered. All I kept seeing is the answer above. Noone respoinded. I have written proof taht Evri has lost my parcels. They are telling me to contact Vinted!!! Noone is helping me, noone is taking responsibilty! Both companies are horrible and VInted is the worst in this case, because they are not even responding to why they did it? who gave them the right to mark someone’s order completed? or why they do not even care that my parcel is lost?? Terrible custumer service and of course they have no way to complain!!!

I have a lot of proof and pictures but I can only upload one.

I want a refund and compensation for the time, emotional and finacial damage that they caused me. Not taking responsibilty and not helping me at all. one of the most horrible custumer service experiences of my life! Not addressing and answering questions and not taking any responsibilty!