According to the Cremonae rules, you - as the buyer - are entitled to post the item back to the seller and claim your money back. So as to do that, for PayPal transactions, you have two weeks after the receipt of the item, unless otherwise specified in the seller’s own rules.
How to indicate a problem:
Step1: On the my purchase page open actions menu, then click on report problem.
Step2: First, please try to discuss your problem with the seller inside Cremonae: click on contact seller and try to get into contact with him.
Step3: If you failed to do so, at the bottom of the page, by clicking on the ‘continue’ button you can enforce your right to receive a compensation via PayPal.
Step4: On the PayPal’s page, after login, please, click on ‘old account view’ at the bottom of the page.
Step5: Please, find the name of the seller and the transaction in the list, then click on the ‘details’ button.
Step6: At the bottom of the page, please, choose the ‘click here to resolve’ link.
Step7: Choose the right possibility and click on the ‘continue’ button.
For Escrow transactions, log into Escrow and make further steps in accordance with the Escrow rules.