I occasionally send text to someone I did not want to send as Siri, or auto suggest fills in people I don't want. (sometimes adds them to correct number type in)
I've tried to diable everything Siri, no luck yet with this.
I use messages on desktop as well as iphone. Nothing in preferences to stop nuisance?
Some of what you are experiencing may be the result of predictive typing. That is, you start to type something and it is automatically completed. You can turn this off in any iOS: Settings>General>Keyboard>Predictive>slide to off.
Also, Siri can be activated by pressing and holding (but not continuously holding) a side button (which and where may depend on the iPhone model). Could you accidentally be doing this before you start typing?
