How can I get the internal colum names of a SharePoint list to appear the same as the display name?

HamidBee When you create a list in SharePoint, "Title" is the only required column in a list and it is a default column in SharePoint with "item" content type.

So, when you import the excel to list, it must be automatically mapping one of your columns to this default column.

Try adding one more column at the start ("A" column) in your excel with column heading as "Title". You can use same value as CustomerNumber in Title column or use combination of FirstName LastName - as per your requirements. Then try importing the excel file to SharePoint list.

Related Read: How to find the Internal name of columns in SharePoint Online? 

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