Amazon India — Amazon prize distribution fake

Sir I got a Letter from Amazon ., Where return i have won 750000 . They called me and asked me to pay 7500 sevice tax 2nd time they called and asked to pay 22500 as GST and he told me that he will pay me my prize money I paid that amount but after sometime he called me again and asked to pay 45000 for NO objection Certificate but now he again messaged me to pay this amount
I trusted and i have paid 30000 total because it was Amazon company but it's big Fraud please take some action against them and if possible refund my money