Amaron — Amaron pro rider battery not working in guarantee period

Amaron pro rider 48 ap-btx5l number 20128f20 eab0229u134803 purchased on 16th march2020 guarantee valid up to 16th march2022. Is not working now in my two wheeler suzuki access125 the guarantee card is misplaced and is not available with me . The dealer of amron is not exchanging the battery in guarantee period only becuase the guarantee card and bill is not available with me . Please let me know what to do only because of lost of paper the product guarantee becomes void ? how to get my battery replaced.