WhatsApp voice notes won't play on ear

Hi everyone, I'm having a problem with WhatsApp, it won't play voice notes when I place the phone on my ear. The proximity sensor is working fine I think since the screen goes black and even though I can't hear anything the seconds on the voice note pass. Call volume is also on max and I've tried pressing the volume up button while playing the voice note but still no good.

Any suggestions?
Thanks!!