Actually this worked for me:
Go to the Gear icon.
Choose Account and Settings, then select the Sales tab.
Under the Invoice Payments section, uncheck the payments options checkbox.
Click on Save and Done.
After that, change the email options for invoices:
Go back to the Gear icon.
Navigate to Account and Settings.
Click the Sales tab.
Head to the Online delivery section.
Choose HTML from the Additional email options for invoices dropdown.
Then hit Save and Done.
