iMessages won’t turn off (iPhone Xs Max with iOS 14.0.1.)

Hello,

I am using iPhone Xs Max running iOS 14.0.1. 

My issue: My iPhone sends/receives iMessages even thought Settings > iMessage is turned off please see attached image for reference).

Seeking your support to help me stop sending/receiving iMessages, as I would like to send/received message as an SMS/MMS only.