Iphone XR starts lagging at 37%

my iphone XR which is only 1 year old and my battery health is 91%. It starts lagging at 37% and then gets shutoff showing the battery is dead and when I plug it in with 3-4 minutes the battery is again 37%, i am not able to recalibrate the battery as i am not able to use it bellow 38%, I tried to hard restart my iphone and i also tried resetting all the setting. Nothing helps, any solution?