# Do not allow entry of Duplicate Bill No of the same Supplier

YouTube: [How to Restrict Entry of Duplicate Bill Number in Purchase?](https://youtu.be/xVxF3AY8hyU?si=afIQ4rubM8U5Y4Q3)

## How to Restrict Entry of Duplicate Bill Number in Purchase?

In this Tutorial, We'll explore when entering a bill number, the software checks against existing bill numbers for the same supplier. If a duplicate bill number is found, an alert will be generated. This feature ensures data integrity by preventing duplicate entries.

#### Steps to Enable Duplicate Bill Restriction

* Navigate to the "Purchase Voucher Configuration".
* Select the option "Do not allow entry of Duplicate Bill No of the same Supplier".
*  Tick the checkbox to activate this validation.

<figure><img src="/files/nr8T8F0AdqLzvOVweqwB" alt=""><figcaption><p>Let's Keep this feature enable and observe it's Impact</p></figcaption></figure>

### **Observe Effect on Purchase :**

* Create a "Purchase Bill".
* If a duplicate bill number is entered for the same supplier, the software will prompt a notification.

<figure><img src="/files/IosP90a9Gb3YFcniiGUw" alt=""><figcaption><p>Prompt for "Duplicate Bill Number".</p></figcaption></figure>

Once you enter the correct bill number, the prompt will not appear.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://kb.logicerp.com/logic-erp-learning-hub-tutorials-and-best-practices/setups/configurations/purchase-voucher-configurations/other-settings-1/do-not-allow-entry-of-duplicate-bill-no-of-the-same-supplier.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.