Why does my phone vibrate while on a call. Galaxy S7 Edge

[AC Question]

I'm on a call and I have another call come in but I don't answer the other call my phone will then vibrate to let me know I missed a call. How can I disable this?

Galaxy S7 Edge

 

[B. Diddy]

Welcome to Android Central! Does it go away if you turn off the Vibrate when Ringing option?