How can I see where the devices are listed for text message forwarding?

BLB_80 wrote:

I have reason to believe that my text messages are being sent to someone else's phone. I don't have the Text Message Forwarding option so I turned iMessage off and then on. When I hit Send and Receive, there isn't an option to add my Apple ID in to see what devices are listed on my phone. Does anyone know why that isn't an option?

Continuity features and requirements for Apple devices - Apple Support