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You are receiving this error because the tables are trying to expand to display the data which meets the pivot criteria. The tables have to grow to to do this.
What you are asking appears to be a question asked over several years on many forums. Unfortunately, there isn't a definitive answer. It seems to be that the pivot table function was not designed to play nice with other pivot tables on the same sheet.
If your pivot tables MUST be on the same sheet, I make the following suggestion; place them side-by-side. You will need to have an idea how many columns will be needed for each table as it expands. Then place a gap between the tables which can allow for the expansion of the table.