Line through volume bell icon

[Jennie69]

I am not sure what I am doing to make this happen, but sometimes my phone won't make a sound and when I check the volume it it has a line through the sound bell icon, even though the volume is at 75 persent. When I increase the volume the line goes away and my phone starts working again.

Any help would be greatly appreciated.

[Uliwooly]

@Jennie69

press the power button > press the volume down/up > set it to vibrate > press the volume down again > now it's set to Do not disturb mode > press the volume up to set it to vibrate mode. 

[Jennie69]

Thank you the quick reply. I tried your suggestion but it is not helping me figure out why my phone sometimes has a line through the bell icon even though the volume is set at 75%. I can't seem to purposley make the bell icon appear with a line through the bell, so I can stop doing it going forward.