Problem with DPD- anybody had a similar issue? (Luxembourg)

Hello guys,

I would like to ask for an advice. I am struggling in my battle against DPD. In April this year I sent my computer, the parcel was signed as fragile at every side but they still managed to destroy it (package with 2 holes, dirty fingerprints at the computer inside, destroyed corners- so it fell down a few times). I sent a complaint, taken pictures etc. After few months of my phone calls and e-mails they accepted to pay me back. But then they rejected paying- saying that parcel was not packed well enough and the value of computer was too high. I am hopeless already, did any of you have a similar issue? Any ideas how to fight them?