Not being able to do thrills

For some reason I can do all the other warm ups except the thrills. My lips just don't do that nor does a pleasant sound come with it. What do I do?

Hi, Kahley! Please see this article for tips & lip trill alternatives: https://www.30daysinger.com/blog/lip-trills-all-about-the-vocal-exercise.

More alternatives here as well: https://www.voicescienceworks.org/sovt-exercises.html.