Sarah Baker says:

Hello,

Most behaviors need to be proofed and have distractions slowly introduced. For example, at home, can you tug in every room? In the yard? Around other dogs? Around food? With any toy? It is normal for behaviors to have to be retaught when moved to new places. Here is a video of how I worked Skeptic through not wanting to play when we moved to a class in a barn with birds: https://baddogagilityacademy.com/course/agility-foundation-for-puppies-and-young-dogs/module-11/video-playing-in-class/ Here is a link to an awesome Bad Dog class just on tugging: https://baddogagilityacademy.com/join-the-complete-guide-to-tugging/
When behaviors fall apart, make things easier and evaluate how well they really know the behavior.