If the "Livery" button is the last button you've pressed on the "Buy" tab, then the the button that bound to the "Purchase" button ("p" by default on PC) actually tries to bring up the "Livery" menu.

Yep this happens to me too. Annoying as hell.

Thanks for the report.

Ah, p was accidentally assigned as the hotkey for the Livery button. It's being changed to i.