Possible transmission issue

We have a 2020 sorento ex has roughly 94k. Last year sometime we noticed the car shifting a little harder nothing crazy. Didn’t think anything of it. Took it at 92k to have transmission flushed for the first time. Now that we’re at 94k and warranty is up at 100k thought we should take it in. Dealership is saying we might have issues with warranty if it is transmission due to not having it serviced at 60k??? I believe it says between 60k-100k?