AJIO - Exchange not fulfilled

Had placed * orders for Brooks brothers tshirts from AJIO mobile app Dated July ** with order IDs - FL********** and FL**********.
Due to size issues an exchange order was placed after delivery of the * products.
The delivery executive who came to exchange refused to do so citing the absence of special AJIO specific tags on the * products. Despite repeated attempts to contact customer service Iwas unable to do so.
The two t shirts received were in exactly the same condition with the same packing and same tags as I had received them. They were worn for checking the size once with the original tags intact and despite repeated requests stating that no tag was removed the issue was not resolved.