Hi,
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It would be easier to find the source of this error if you could provide us with a reprex. A reprex consists of the minimal code and data needed to recreate the issue/question you're having. You can find instructions how to build and share one here:
The error now occurs because there is no end_hours in your data frame, but you show below you create this using the clean_dfs mutate. However, this line seems problematic:
clean_dfs <- new_binded_dfs_no_dups
You overwrite the clean_dfs with data from another variable, so even if you did change it before, it will revert to this one (and thus lose the mutated variables probably).
Please provide a reprex if this is not the issue
PJ