You enter an Other payment for £120 for some office supplies twice by mistake. Your last VAT Return included both transactions.
Your bank account balance is now £120 less than it is in real life
You've declared an extra £20 on your VAT Return
When you report on office supplies purchases, it's £100 more than expected
To make sure your bank account and VAT Return are correct, you enter an Other Receipt to reverse this. You use the same date, amount, ledger account and VAT rate.
Your bank account balance increased by £120 and is now correct
Your next VAT Return gets adjusted by £20
Your office supplies are now £100 less and are correct
NOTE:
Any corrections that you make will appear when you create your next VAT Return.