Would be good if you could post a picture of the board.
I would not fault the official documentation, because all the Arduino branded boards use A4 and A5.
What can get confusing is that analogRead() will accept both the Ax designation and x without the A to refer to the same analog pin (as an example A4 or 4), but the other I/O functions (pinMode, digitalRead, digitalWrite) use x to refer to a digital pin, needing the Ax designation for digital use of the analog pins. (there are digital pin numbers for the analog pins, but they are not portable across different boards).