[ExcelExporter] : Error while call java action = GenerateExcelDoc in Mendix Learning Path : Export Data with Excel

Hi, I trying to follow the Learning Path of : https://academy.mendix.com/link/module/136/lecture/1267/7.3.2-Entities,-Microflows-and-Excel-Template-Configuration But in testing, I found an unexpected error. I trying to debug and found its error when call Java Action = GenerateExcelDoc after that it check if $MxCellStyle/Format = XLSReport.CellFormat.Number? but my variable of MxCellStyle/Format = General. So, it returns an empty string then an error. Please help me what is the root cause and how to fix it? Mendix Version = 8.18.0 Thank you,    
1 answers

ANSWER: refer to this question : https://forum.mendix.com/link/questions/104656

This issue caused from multiple version of poi file.

Just rename or delete poi*.4.1.1.jar files and re-run again.