Index Match not automatically updating?

This is the first time I've encountered this issue. I am using index match in one workbook to search the values/data in another workbook.

I noticed that if I update the source workbook, the other workbook doesn't automatically update with the new values.

I have to go to the table/column with the index/match formula and click enter. Once I click enter, it'll ask me to search for the source file. I can either click on the source file or I can click cancel and the index/match will automatically update.

There's no other pop up asking me for permissions or allow anything, so I am not sure what I should do so that this would allow for it to automatically update without having to go back and do this process every time.