I ran fragment insertion as seen in the tutorial. I used the Silva 128 provided tree and alignment. My insertion tree was created, and I filtered my feature table. However, once I get to the classify-otus-experimental step and use the Silva 128 consensus 7 level taxonomy, I get the following error:
Not all OTUs in the provided insertion tree have mappings in the provided reference taxonomy.
Could you please provide the commands that you are running and the full error message (though that message seems clear enough, the full message may provide better context).
I should add a word of warning: that method is experimental and does not really perform particularly well for taxonomy classification, so I would really recommend using the methods in q2-feature-classifier instead.