Hi @student5 ,
Providing a reproducible example will greatly help. In your case, sharing a minimal dataset as well as the list of packages you use would greatly help.
Why reprex?
Getting unstuck is hard. Your first step here is usually to create a reprex, or reproducible example. The goal of a reprex is to package your code, and information about your problem so that others can run it and feel your pain. Then, hopefully, folks can more easily provide a solution.
What's in a Reproducible Example?
Parts of a reproducible example:
background information - Describe what you are trying to do. What have you already done?
complete set up - include any library() calls and data to reproduce your issue.
data for a reprex: Here's a discussion on setting up data for a reprex
make it run - include the minimal code required to reproduce your error on the data…