Shocking service

i ordered a quantity of 5 of the same item. 4 was delivered correct, the 5th a different product. Initial communication was good and the exchange was approved. However I never received the correct item after I sent back the incorrect unit. I made use of the collection point. The return item was sent to a different province. Subsequent communication is shocking. No phone number, just reference numbers by mail. You replay "above the line" as requested but no response. It has been 2 months since the initial purchase. Online tracking shows return concluded. Well it is not.