Recalled iPhone

I brought my iPhone to a authorized repair shop because my screen all of a sudden started showing green bright lines and some areas of the touch screen could were not responding. I was told that the iPhone was “recalled” and I should have it replaced. How do I go about this? My iPhone was in perfect condition - or so it seemed - never dropped, no scratches, never serviced. It’s a X version iOS 14.7.1. Any help most appreciated. Thanks!