> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://support.zoombucks.com/sitemap.xml
> Use this file to discover available pages before exploring further.
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# Why do I receive an error message when redeeming a reward?

You will not be able to redeem a reward if our security system detects suspicious activity, such as the usage of proxy servers or VPNs. If you encounter this issue, please contact us through the **chat function** at the bottom right of the page for assistance.

In addition to security checks, you must confirm a phone number that matches the country you reside in. If you need to update your phone number, follow these steps:

1. Click on the **hamburger menu icon** (☰) located in the top right corner of the navigation bar.
    
2. Under **Others**, select **"Settings"**.
    
3. Scroll down to the **Phone Number** field and enter your new phone number.
    
4. Please note, you can only change your phone number once every **7 days** for security purposes. If you are unable to update your phone number, please wait a week and try again.

If you continue to experience issues with your phone number, reach out through the **chat function** on the bottom right of the page, and we’ll be happy to assist you!