Out Of Position Players

Why is that in every lobby I get in, I'm stuck playing out of position? I chose to make a playmaker after playing as a stretch big to see how it was, and in The One... I was having fun, setting up teammates and playing solid D on my man. However, Online... I'm stuck playing at random positions, guarding guys that are bigger than I am and I hardly see the ball at all.... and when I do get it, no-one else is open for me to set them up, so I have 0 choice but to shoot it. It sucks when I'm the only guy playing solid D on my end & the guy I have to guard is Porzingis. It's stupid & I don't get it at all. I'm a PG, why not play me as one? I saw a similar issue as a bg man where I was the only big guy on the court, but at least then I could rebound the ball & get into the post easier. Has anyone else dealt with this online BS?