Model KNN: error unused arguments

Hi everybody!

I write a KNN model and my script is:

library(class)
library(ggplot2)
library(gmodels)
library(scales)
library(caret)
library(tidyverse)

db_data <- iris
row_train <- sample(nrow(iris), nrow(iris)*0.8)
db_train <- iris[row_train,]
db_test <- iris[-row_train,]

unique(db_train$Species)
table(db_train$Species)

#KNN
#-------
model_knn<-train(Species ~ ., data = db_train, method = "knn",tuneGrid = data.frame(k = c(2:20)))
summary(model_knn)
#-------

#PREDICTION NEW RECORD
#-------
test_data <- db_test
db_test$predict <- predict(model_knn, newdata=test_data, interval='confidence')
confusionMatrix(data=factor(db_test$predict),reference=factor(db_test$Species))
#-------

but when I run the model_knn I have this error:

Error in train(Species ~ ., data = db_train, method = "knn", tuneGrid = data.frame(k = c(2:20))) : 
  unused arguments (data = db_train, method = "knn", tuneGrid = data.frame(k = c(2:20)))

I can't understand why, since it was working perfectly until yesterday.
Can anyone tell me why I have this error today? How can I fix it?

Thanks

Is your session clear when you try this, or could you be maintaining state from old code or old sessions ?
what do you see when you do :

getAnywhere(train)

I tried closing and reopening the session and now it seems to work