Hi all! I have been playing around with the caret package and tried a LASSO regression model on the R dataset Lake Huron. However, when I run my model, I get the error message "model fit failed for Fold1: x should be a matrix with 2 or more columns". Could anyone elaborate on what I'm doing wrong? I will post my code below. Thanks already for the help in advance!

```
library(caret)
library(glmnet)
df<-as.data.frame(LakeHuron)
df$Time<-c(seq(1875,1972,by=1))
set.seed(1985)
index <- createDataPartition(df$x, p=.8, list=FALSE, times=1)
train_df <- df[index,]
test_df <- df[-index,]
ctrlspecs <- trainControl(method="cv", number=2,
savePredictions="all")
lambda_vector <- 10^seq(5, -5, length=500)
model1 <- train( x ~ Time,
data = train_df,
preProcess = c("center", "scale"),
method = "glmnet",
tuneGrid = expand.grid(alpha=1, lambda=lambda_vector),
trControl = ctrlspecs,
na.action = na.omit)
```