Notifications silenced on iphone

Re: "When a message is sent to my phone the sender gets notified that my I have notifications silenced.

How to I change that".

To Check Phone is not in "Silent" mode:

How to put your iPhone on vibrate, ring, or silent mode - Apple Support

______________________________________

Check if you do have notifications turned off:

How to: Use notifications on your iPhone or iPad - Apple Support

Eg: says:

To manage your notifications from the Lock Screen or Notification Center:

1. 1. 1. Swipe left over an alert or group of alerts.
      2. Tap Options, then select from these options: 

• • • Mute for 1 Hour
    • Mute for Today
    • View Settings
    • Turn Off

You can also tap View Settings to change your alert styles or alert settings for a specific app.

_______________________________________________________________________________________

Else:

Seems like you could have "Do Not Disturb" turned on. If so tap the Focus that is set to turn it off

How to: Turn on or schedule a Focus on iPhone – Apple Support

All the best :-)