I have built a report using pivot table for a client and he has encountered this problem where if you simply refresh the pivot, it works fine but if you click Refresh All from the Data tab, it gives this error:

“The PivotTable field name is not valid. To create a PivotTable report, you must use data that is organized as a list with labeled columns. If you are changing the name of a PivotTable field, you must type a new name for the field.”

As per my research, the sole reason for this error is, if there are one or more columns in the source data without headers. In my case, the pivot table is based on a Data Model instead of a simple excel table or a range of data. Even then I looked at every column of Data Model tables but found nothing.

Can anyone suggest what could be the reason?