Transmission may need replacement?

Hello,

Is this something that has been happening for sometime or just happened?
Is there any error light illuminated on the dash? Like a check engine light?
If so you might want to get it scanned. As that will help narrow down the issue.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

You also might want to have the transmission serviced just incase you have contaminated fluid:

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

I have attached the transmission replacement guide for your reference.

Please let me know of any questions.

Thank you.