If you need to adjust the rate within a draft invoice, you are able to do so. Head to the invoice in question, select the overflow icon to the right hand side of the item you wish to change and click edit.
Then select the individual line item you wish to adjust and click on the pen icon to make the adjustment. It is also possible to delete individual line items, or remove the item as a whole.
⚠️ You can only edit the rate of a draft invoice. Once an invoice has been issued, you will be unable to change it.
For more information on invoices, see the article Invoicing.