Lacona, I don't know what that code is. It seems only barely related to your original question. Please remember I have none of your context or data.
If this is still the same issue, please read the help file indicated and also read the instructions at the link posted above (here it is again).
I am trying to help, but I really need you to help me help you!
Can you perhaps post the output from dput(head(name_of_your_data))