I keep losing the ringer of the phone. When I get a phone call it does not ring. How do I fix it.

[ayesha0786]

How do I fix the sound of the i phone 5 s . it keeps losing the sound, does not ring when I get phone calls. I tried fixing it many times, it does not work.

[Fdubiel]

I had that trouble and the switch on the side of the phone maybe set to vibrate only