For a customer portal invoice query, send the invoice number, the specific line you question, the expected amount and only the files needed to explain the difference. Ask for a concrete decision. A large attachment bundle without a clear question gives the supplier more documents to read without identifying what needs correcting.
This workflow is for a customer's finance contact and the supplier reviewing that request. The evidence matrix and message templates below are original operational aids, not a tested customer case or a legal determination of what is owed.
Build a Minimal Invoice Query Packet
Start from the invoice in the Customer Portal. Identify one disputed item rather than describing the entire account as incorrect. Record currency, issue date and any relevant service period so the reviewer can distinguish a billing error from a different reporting period.
| Question | Useful evidence | Leave out unless needed |
|---|---|---|
| Wrong quantity or rate | Invoice line plus accepted scope or rate excerpt | Entire unrelated contract archive |
| Payment not reflected | Amount, date and relevant payment reference | Complete bank statement with other transactions |
| Wrong billing details | Incorrect field and requested correction | Identity documents without a clear reason |
| Possible duplicate charge | Both invoice numbers and matching service periods | Unrelated supplier invoices |
This is a suggested selection method. Mask unrelated personal information in screenshots while preserving the identifiers needed to investigate. Keep an unedited original in your own records; label a cropped or redacted copy accurately.
Explain One Difference With Numbers
Assume a fictional consultation invoice lists three sessions at EUR 120 each: EUR 360 before any applicable tax. The agreed scope says two sessions, so the customer's expected base amount is EUR 240 and the questioned difference is EUR 120. The supplier must still check whether a third session was authorized; the calculation alone does not establish an error.
A useful message is: “Invoice [number], consultation line: three sessions at EUR 120. Our attached scope excerpt covers two sessions. Expected base amount: EUR 240; difference: EUR 120, before tax. Please confirm the third session's authorization or explain the correction. Contact: [name].”
Attach the invoice line and the relevant scope excerpt. Do not ask for a refund, a changed invoice and a canceled subscription interchangeably: those require different decisions. The refund-request workflow explains the separate customer request stage for an already-paid invoice.
Keep the Evidence in the Portal Conversation
PayRequest's Support Requests documentation describes customer portal tickets, file attachments on replies and request categories including billing questions and invoice/order corrections. Customers can add files when replying in the portal; the documented limits are ten files per reply and 20 MB per file.
Open the relevant request, add the explanation and files to a reply, and review the queued attachments before sending. A question alone may be enough to start the conversation; additional evidence can follow in that thread. Use a descriptive filename such as invoice-number-scope-excerpt.pdf rather than screenshot-final-final.png.
The supplier should confirm that the request belongs to the correct customer and invoice before making a billing change. Place private investigation notes in an internal note, which the documentation distinguishes from customer-visible replies. Keep the customer-facing explanation understandable without access to those notes.
Close the Question With a Verifiable Decision
A ticket marked Resolved is a conversation status. Check the relevant invoice or credit record separately before saying the bill changed. A viewed ticket or a sent reply is also not proof that the customer accepted your explanation.
Use this closing template: “We reviewed invoice [number], line [description], against [evidence]. Decision: [explanation/correction]. Billing record: [identifier and verified amount]. Payment action: [required/not required/still under review]. Owner and next update: [name/date].”
If the supplier needs another document, name it and explain why. Avoid requesting the customer's full bank history to investigate one receipt. For recurring document questions, the month-end invoice checklist offers a separate completeness workflow.
Rehearse One Clear Invoice Question
Review Support Requests, then connect the conversation to the underlying invoicing records. When setting up this workflow for your customers, create a PayRequest account and rehearse one example with a clear question, relevant attachment and explicit closure.
Prepared by the PayRequest Team with AI assistance. Published product documentation was reviewed on 10 October 2026. The matrix, templates and amounts are illustrative; no customer result is claimed.


