Generate invoices for customers

I need invoices generated for our customers for last month. Use the customer list in Billing — start with Acme Co., Brightline LLC, and Delta Health — and produce PDF invoices that list items billed, tax, and the net due. Send the PDFs to finance@ourco.com for review, then to the customers in that order, and set the due date to 30 days from today. Confirm all invoices include the company legal address and our VAT number before sending.

Before I send these invoices to customers, make them easy to pay and hard to dispute. Put the total due and the payment link on the first page, move line-item subtotals under each product so pricing is obvious, bold any one-time fees, and add a single sentence near the top that explains why this charge appeared this month. Flag any invoices where the billing contact on file differs from the primary account owner.

I just generated invoices and Acme Co. replied saying they never ordered the extra support hours. I can’t tell if sales logged the hours or our billing double-counted them. The invoice already went to finance for approval. Who should I call first, what evidence should I pull immediately, and how do I patch the invoice so cashflow isn’t delayed while we investigate?

Every month we waste hours reissuing invoices because disputes about usage or wrong contacts come up. Sales, support, and billing never agree on the source of truth for usage. What single habit should I change to cut reissue time by half and prevent the same dispute from recurring three months in a row?