Null Values in query editor

I have a folder in sharepoint that i get data from in power BI by transforming data/ combining files. I then have a power automate flow that adds data daily into the sharepoint folder.

When i refresh the data, the original data that i used is all showing correctly however the daily data that is being added is showing as "null" values for all columns. 

Both datasets are Microsoft Excel Comma Separated Value Files

Does anyone have any idea why this is?