Buyer wants refund after i nearly finished the order

[filusaad]

Hi there im a level 2 seller on fiverr. so a buyer orders my gig to make a video for him, it had 4 days delivery date, and now 3 days passed i had nearly finished making the video, and the buyer changed his mind and wants a refund now, what should i do now please help, he made a dispute to cancel the order