Hi @Laura1
You can export your complete nominal activity by following one of my previous posts, which can be found here.
As @FaradayKeynes mentions, it’s likely that there are prepayments on one or more client accounts which would be affecting your figures. If you view the historical report and export the data, there is a breakdown of the figures which should hopefully explain it.
Of course, if you need further help, please don’t hesitate to ask - it’s why we’re here 