Transmission shift points

Hi, have a 2016 Chevy Malibu Limited with 46,000 miles on it.  The car
wants to rev as hi as 3000 rpm with a slow take off before it will shift into 2nd
or 3rd gear.  The other gears are just as bad.  If I go up the slightest hill the
rpm goes higher or sometimes will not shift at all in 3rd gear and up.  On the
freeway, it will not go into 6th gear unless I'm doing 73 mph or faster, and if
it's the slightest hill it will kick down to as low as 3rd gear making the motor
spin as high as 5000 rpm.  Is there a way this can be adjusted?  I can take
over the shifting and the car moves just fine and will go into the gear I ask it
to and stay unless I slow down.  The dealer wants almost $300 just to take it
into the garage with repair cost on top of that.