Unfortunately, the webshop Vinted cannot be reached by phone. However, you can contact them through the VintedApp. Through the sales agreement in the Vinted App you will see a 'Help' button at the top right. If you select it, some questions will follow. Find if your question is listed here, if not, you can select a similar question and scroll all the way down. Here you will find an empty comment field, where you can describe the question or situation.