Datasource column name changed

Hi PBI, If a column header name for my source data changed, how to I update PBI so moving forward I use the new header name. the top table was the 'OLD header' in yellow. This header is now changed to "ESC GM (qta)"When I rename the header in PBI, I get this error,. It does appear PBI does not like the new header. I want to use "ESC GM (Qta)" moving forward