When you pay an invoice in a currency that varies from the base currency of the accounting file, it is quite common that the fx rate used by the accounting file will differ from that used by the payment provider.
When this situation occurs you will be left with an over or under payment which is due to fx:
In this instance we can see the original payment of £15,000 was for a USD invoice of $20,000, but at the time of payment, the fx rate used by the accounting file shows £15,000 = $18,690.15 leaving an fx variance of $1,309.85 which will need to be adjusted. We do this by clicking the blue Edit payment distribution button to the left of the total and then switching currencies by clicking the currency sign:
And then inputting the amount as per the invoice:
This will then show the bill as being fully paid:
We then need to account for the fx when the base currency of the accounting files of the paying entity and the receiving entity differ (in this case GBP and AUD), which will impact the intercompany loans.
This can either be solved by a manual journal in your accounting file, or if you are a Mayday balancer user, you can head to the relevant intercompany loan and one click post the fx adjustment using this button on the dashboard:
More information on that can be found in this helpful article