After you've raised an invoice and sent this to your customer, the next step, unfortunately, is paying your supplier. When you make payment for the invoice you will need to reconcile the invoice against the bank transaction for it to show as paid.
Please follow the steps below on how to do this.
First up, find the unreviewed transaction in the transactions tab.
Next, click into the category tile.
Finally, select the outstanding invoice to allocate the transaction to the invoice.
Once you do this, you can then approve this transaction.
After this, the invoice with show as paid with the transactions linked.