How to add service date for invoices items?

I’m running a gardening service company. Each invoice must show the date each service was performed.

I’ve created an item for each service, customers and now trying to make my first invoice.

How can I add the date the service was performed to each item line in my invoice?

Here’s the manual page describing custom fields:

In this case, you’ll want to customize the child doctype Sales Invoice Item.

Thanks for your quick reply.

On ERPNext v13.0.0-beta.11, I went to: Customization → Customize Form, then searched for “Sales Invoice Items”.
Then clicked “Add Row” in the bottom of the table and filled it with:

  • Label: Service Date
  • Type: Date
  • Name: (will be auto-generated after saving to service_date).
    Then clicked on its pencil icon to edit it and set enabled “In List View” as well as “In Preview”.

Then clicked on “Update”.

Doing this seems to have broken the UI:

  • I can’t go anymore to any of the other Form Types in “Customize Form”.
  • It always says “Not Saved”.

After rebooting the docker image and trying to save the Sales Invoice, I get this error message:
Error: Document has been modified after you have opened it (2021-02-07 16:06:45.037952, 2021-02-07 16:06:45.203558). Please refresh to get the latest document.