Apparently this has been an issue for some people since iOS 14.
< [appletoolbox.com];
Follow These Quick Tips To Get Sound Back On Your iPad!
Toggle Mono Audio On and Off
Plug and unplug headphones for devices with a headphone jack
Toggle your iPad’s Side Switch (if applicable)
Change your iPad’s Side Switch Setting to lock orientation instead of mute
Open Control Center and adjust Mute or Volume from there
Toggle Bluetooth Off and On
Check the Do Not Disturb is off
Restart or force restart your iPad
The one I bolded was the second thing I tried and that was the solution. Somehow the volume setting in Control Center had been set back to zero. This happened to both her iPhone and her iPad the same day. Weird.
My life goes smoothly and in regular intervals