Performance operator not working

Hi, has anyone tried to do a stock sentiment analysis using news headlines? I am currently working on such a project and have used Extract Sentiment Operator, as well as Process Documents from Data (inside: tokenize, filter tokens by length, filter stopwords), I have split the data, used k-NN, applied the model, but Performance (Binominal Classification) does not work for me as it says label and prediction must be the same type but are binominal and real. Does anyone know if there is a way to fix this? Or has anyone worked on a similar thing and would help me out?