Fedex Express Transportation And Supply Chain Services India Private Limited - Fedex is not refunding my double payment

I ordered a toy from china, fedex has shipped my toy, when it reached bagalore, I got a mail from fedex saying that, I need to clear some amount then only they can deliver the product to me, and they shared the link to pay. I paid the amount online, but when the fedex executive delivered the parcel, he demanded the amount again stating that, you will be getting refund, and he denied to give the parcel without that payment. I paid the amount. After that I tried to contact fedex for the refund, they are just passing the time without initiating the refund. I vexed up following up with them.