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# 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.


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