Data format error on refreshing data from Excel

I am also having this issue. I have an org code column with an overwhelming majority of numeric only data. A tiny subset has Alphanumeric. On refresh, it keeps changing the data type to numeric, even after manually changing to text. Even if I go to the supporting excel spreadsheet and force the data into text at that level, the import still converts the data to a number. I even tried sorting the dataset to force the cells with alphanumerics to the top (hoping when power bi went to preview, it would adhere to the sort order and recognize the datatype)....no luck.