Still only cold the passenger side

This sounds like a blend door issue so that means we need to start with checking this by removing it and moving the door manually. If it is able to get cold, then the actuator is likely the issue.

I am attaching the process from the manual below but here is a guide that will help with this:

https://www.2carpros.com/articles/replace-blend-door-motor

Please see the process below and let me know if you have questions.

Thanks