Changing Name Of Pivot Table

I seem to have a small problem with a Pivot Table on a file that we get weekly. I've built a macro to run across the file to format it and refresh. The problem is, sometimes it fails because the Pivot Table is listed as "PivotTable1" and sometimes it comes through as "PivotTable2". I'd like to amend it so that regardless of it's name, it can be renamed to "MainPivot" or something similar.

All I can get upto so far is:

ActiveSheet.PivotTables("PivotTable1").Name = "MainPivot"

Is there anyway to amend the macro to select the pivot (there's only one on the sheet) regardless of what it's initially called?

Thanks!