Combining SharePoint Excel Files but Removing rows beforehand

I am using PowerBi to combine excel files that are placed in a SharePoint Folder, however everytime I do, I receive an error. I beleive it's because of the 03/03/2020 part in the first row. Every excel fiel is the same format and structure. Everytime I combine it, it only Transforms the sample file. For Instance, the file name 03.01.2020 is the same file and is transformed with the Source.Name in the first column....but gives errors for all the other excel files. Is there anyway to clean up the excel files before combining them within PowerBi? Below is an example of what the excel file looks like.