2021 Kia Rio

So I have a 21 Kia Rio with 74k miles on it . Runs fine. I keep up on my maintenance like it’s going out of style . It’s my daily driver and noticed my RPMS this last week have been acting up . It was jumping up and down granted I was going uphill and downhill which I’m sure is normal but also it’s been getting “stuck” at 2000 rpm doing 45 on flat road usually runs at 1100 and I also noticed my rpm’s would spike when braking going downhill. My mpg has dropped some too . I am taking into the shop tomorrow . Does anyone have any idea . It has one of those stupid CVT transmission