That’s not the case. I live here in INDIA and here there are service centres in most of the cities. Its not in every city because the profit margins of oneplus are quite low as compared to samsung or the htc or asus, lower the profit margin, lower capable the brand is in providing services and other aspects. Also they just launch one phone a year, so their growth is relatively slow.
Amazon will not attend your complaint, its because amazon is just a online shopping site and not the manufacturer of the phone, the warranty is provided by the manufacturer.