failing 3 months hearing test

Hi, jus went for poly check up and LO failed her hearing test. She only turn her head once to the sound. We tried at home and it took many tries for her to turn. I know she can hear as she does react to sudden loud sound and do response (smiling, talking back) to us when we make sounds with her. Just wondering is it her reaction normal? What happen if she fail her hearing test next month?