Cash summary not matching gst worksheet


my cash summary income for oct-dec periods matches income received and bank statement.
but the income on the gst calculation worksheet is less.
I cant wrap my head around how or where to find this difference?
It isnt an amount of a single invoice or something like that. and the payment receipts match the bank deposit amounts.

Thank you for your help

Look for entries without an appropriate tax code applied.
You can sort by that column to speed your search

You could look at the Tax Transactions report to see what is different there compared to your bank records.

thank you for replying.
I am unsure as to where to search for that?

But what confuses me is that the cash summary income is matching what we have received but then the gst worksheet has a lesser amount. but that should be showing all income gst inclusive or not.