iPhone: the WhatsApp voice note suddenly stops in the middle of the game

So this has been going on since I bought my phone. Every time I tried to play voice notes on WhatsApp, they would suddenly stop playing and the screen would turn off. I would try to play again to get the same result and, therefore, to listen to the full voice note, I would have to keep pressing the play button every time it stopped suddenly. What do I do about this?