Order Receipt Problems with Mango

I placed an order for two items through the Mango app on November 11, 2023. I chose the option for in-store delivery. On November 13, I received an email stating that my order was delivered to the store. When I went to the store two days later, I was told that the items had not arrived, and I was advised to come back in a few days. When I returned a few days later, the items still had not arrived. I was directed to customer service. For 36 days, I have repeatedly called customer support, and I was told that the store would contact me, but there has been no communication. When I tried to initiate a return, I was informed that returns are not possible during this period. It is unclear where the items are, and I have not received a satisfactory outcome from any customer service representative. This is the worst shopping experience of my life.