Now, just putting an Excel with some crude data in it won’t really be identified in the Canvas App you are making. Perhaps you’re missing something.
Let’s say, I want to read an Excel file from OneDrive For Business into my Canvas App, I select the Excel file from the OneDrive for Business connection like below –
But, I’m treated with the below error while making a connection – 
Correcting…
Continue Reading priyeshwagh777’s Article on their blog
Correctly connect to an Excel file in a Canvas PowerApp – D365 Demystified
Facing trouble connecting to Excel file from a data source? Check this out. Perhaps this is what you’re missing.
Blog Syndicated with priyeshwagh777’s Permission