Letters BBC appearing randomly in texts I’m sending

I have a one year old CR iPhone. The capital letters BBC appear randomly in my texts got no reason. It is not predictive text. The BBC beats no relationship to what I am typing. And the letters and words surrounding it are oftentimes on the other side of the keyboard. So it’s not like my fingers slipped. I catch it in time and backspace them out before hitting SEND. WHATS GOING ON AND HOW DO I STOP THIS? Oh