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Before you write

Most questions are answered by the in-app Help page (InvoiceAnvil, then Help, in your Shopify admin): how the legal numbering works, how to collect your customers' VAT numbers, what each plan includes, and what is printed on a document.

To help us help you faster

• Your .myshopify.com domain: we cannot look anything up without it.
• The invoice or credit-note number concerned (INV-00042), or the order name (#1042).
• What you expected, and what happened instead.
• A screenshot if the issue is visual.

Common quick fixes

• An order was not invoiced. Invoices are created when the order is marked paid; pending and unpaid orders are not invoiced. On the Free plan, only the first 15 orders of each month are.
• The buyer's VAT number is missing. Shopify's checkout has no VAT field. Add a cart-attribute field to your theme; the in-app Help page has the step-by-step snippet.
• The number prefix cannot be changed. A legal series locks once its first document is issued. That is by design: a sequence has to stay continuous.
• Wrong company details on an invoice. Issued documents are immutable snapshots. Fix Settings for the future, and correct a wrong invoice with a refund, which produces a credit note.

Feature requests and bugs

Both are welcome at the same address. Feature requests genuinely shape the roadmap, and confirmed bugs are prioritised ahead of any feature work.