Amazon India — imei number not mentioned in amazon invoice

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Gurgaon, Haryana, 122001

I have bought oppo f1s with one year screen protection (Onsite go) items from amazon india. There is issue with my mobile phone screen. When i downloaded amazon invoice from amazon site. There is no imei number mentioned in that invoice. Hence, i couldn't be able to claim from onsitego for screen replacement due to fact that imei number issue. When i called to amazon india customer care. They asked me sorry for the inconvenience and said that issue will be resolve within 7 working days. I am following since last two months. However, amazon india has not been given correct invoice with imei number. I have loosen my faith and confidence from amazon india.

I don't know how do i proceed to get proper support from amazon.

Regards