IndustryBuying.com — multiple payments and not possible to reach customer care

Due to an error in their app the payment amount for an order of a webcam was deducted three times from my account. Tried to contact them by phone but calls always getting disconnected. Then wrote an email with payment details and the request to refund the money. No reply! Instead they concerted the faulty payments into additional orders, so now i have the three orders for webcams. Tried to cancel two of them, but the website responded with "cancellation not possible". So again i wrote an email to customer service asking them to cancel two of the three orders. No reply again. On top, my order which had a delivery time of 4 days hasn't even started to be processed after 5 days. And another of my orders is already pending for 11 days.