Speaker on bottom of phone not working

Last night my phone volume button was getting stuck going down. I managed to fix it and get it unstuck myself but in the process I turned my phone off and due to the button being stuck it booted to a black screen with text and then into safe mode (I hadn't done this before and wasn't sure how I had done it but got back to normal). Today I noticed that my phone was very quiet at full volume and upon closer inspection only the speaker at the top of the phone is putting out sound, the one below is not making any noise at all.