iPhone 13 battery draining rapidly and shutting off

Today I went to an authorized apple store in Ecuador, because my iphone has a bad battery, it drains immediately, and the store told me that from 7 to 15 days I could do the battery change for 130 dollars, I was told that a batch of iphone 12 and iphone 13 went bad and that in some cases the battery change could be free, I did not get my hopes up but there is a possibility, the question is how do I know if I iphone 13 applies? (I understand that with my serial number, but where or who?) Thank you for your answers.