Hi @EX_Tenn,
Ideally you'd give us a reproducible example (reprex) of your issue as a starting point. A reprex makes it much easier for others to understand your issue and figure out how to help. A lack of a reprex just makes it much less likely others will reply.
If I had to take a guess, there may not be a method implemented for fitted and/or resid for the type of model you are using, but without a reprex it is hard to know for sure!