Open file from sharepoint - getting a blank file

Hi everyone!

I would appreciate you help (again) understanding what am I doing wrong.
So, I need to open a workbook base on the date in filename (something like "filename_15022018.xlsx") from a sharepoint site.

I am using this:

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The annoying part, more than just not opening the right file or not opening at all, is that this runs perfectly, finds the right file and open it... but blank! It is a 30Mb file and every time I run this it opens as a blank workbook. How?

Thank you all in advance.