When I type, it sometimes automatically puts the last word of my last sentence at the start of my next sentence. It happens on multiple apps. How can I stop this?

An example:
'Hello, how are you' (send message)
'youHaven't seen you for a while'

It happens not always and I think I don't press a certain button. Autocorrect is of and I use g2's standard keyboard. The phone is new, it happened out of the box.