Automatic Transmission won't shift on my 2009 Kia Borrego Lx

What is your question?

I just bought my 2009 Kia Borrego Lx about 3weeks ago. I have done a Tranny Flush about 10times bc the Tranny Fluid was Milky & the Tranny wasn't shifting. I can get it to kinda shift & go take it around the block a cpl times & then I come back & park it & try starting it & doing it again & then my car won't shift or move. So it's picking & choosing when it wants to do this, but mainly choosing to NOT shift & go. I DON'T feel that it's a BAD Tranny, I feel like it's something else, but what idk?! I've been doing research & research to try & find out what it cld possibly be & I haven't found much help yet at all. Research I have found so far is a LOT of ppl are complaining of the Tranny as well & why it's NOT on recall?! All I NEED to know is IF there is 1or2 PCM's to this car & I NEED to KNOW what this Tranny Problem cld possibly be! Any HELP wld be greatly APPRECIATED!! TY 2009 Kia Borrego Lx Owner who should have done Research 1st!

What makes this problem better or worse?

Idk it just picks & chooses when it wants to shift & when it doesn't.

How long has your 2009 Kia Borrego had this problem?

A few weeks since I bought the car.