My client can't see bank transfer option anymore when I sent them invoice just wondering why this happened

Ask your client to open the invoice link in an incognito window. This ensures the page loads without interference from browser history or cached data.

If the issue persists, please review the Online Delivery section under the Sales tab in Account and Settings. Verify that the Additional email options for invoices field is set to Online invoice. If it is not, update the selection and click Save.

After that, resend the invoice.

Let me know if you have any further questions.