Huawei — service denial letter

Address:

2087 Belgium square opp linear bus stand ring road Surat, Surat, Gujarat, 395002

I purchased brand new mobile from amazon huawei p20 pro blue at the amount of Rs.64999 on date 11th july, 2018.
My order id is[protected]. Last month my figure print scanner stopped working and then i
visited the service centre of huawei surat and there they told me that your warranty has expired.
But according to the bill warranty should expire on 11th july, 2019 but your service centre guys are saying that your warranty has expired. So the mobile was pre activated before i purchased it (Activation Date :[protected]. I also contacted amazon regarding this issue, they asked for the denial letter from huawei service center and
i got only acknowledgement slip from service centre saying that there is nothing called denial letter.
Amazon is continuously demanding for denial letter and only after that they can help.
I also called huawei customer care number which is [protected] they also said we can not provide any of this latter.
then where i have to ask for it ??? no one is help me. its is not my fault that mobile is pre activated or used.