It's hard to know for sure without a REPRoducible EXample (reprex) but maybe your problem is with your date format, the default is %Y-%m-%d if your date column has a different format, then you need to specify it with the format parameter e.g.
as_date(data$column, format = '%m-%d-%Y')
If you need more specific help, please provide a reprex. A reprex makes it much easier for others to understand your issue and figure out how to help.
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