Each branch sends its own file, with the columns in a different order and “Sales (RM)” spelt three ways. Add the files and get one merged sheet, a total by branch, and a check of anything that does not line up.
Runs in your browser. Your files are never uploaded.
Three checks so the monthly total is right the first time.
Capitals, spaces and brackets are ignored when columns are matched, wherever each branch put them.
A Source File column is added, so any number in the summary can be traced back to the branch that sent it.
A column that only some files have is kept and called out before it quietly throws off a total.