Workbook Crashes Upon Closing Userform (Userform Updates Pivot Table Source Data)

Hi Everyone,

I'm having an issue with a simple userform crashing my Excel application. This userform simply allows the end user to add an entry to an Excel table on a separate page. This table acts as the source data for a pivot table/chart.

The macro I use to update the table works like a charm. The userform does not crash when running the macro. However, when I close the userform (by clicking the "x" in the top right hand corner of the userform), the entire application crashes. I've included my code below. Any help would be much appreciated.

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Note, that everything works fine and nothing crashes if I simply "hide" the userform with another command button. But exiting out of the userform using the "x" still crashes the program