R help - Apr 2019 - Problem in using train() function in Caret

Hi, Everyone,
I have another question with using train() function in Caret package. When I
coded
tree.spam.cv <- train(Label~., data = train_spam_toke_df, methods =
"rpart", trControl = cv_spam_control,
                   tuneLenght = 7)
it gave the error as follow,
Error in terms.formula(formula, data = data) : 
  duplicated name 's.i.m' in data frame using ?.'
I am not sure if there is any bug with my software. I used to have no problem
when I wrote lm(y~., data = data1)

Can someone help me with this problem? Thank you so much!

Chaoyang