Error while adding WhatsApp channel using Twilio

Hi,

I am trying to add a WhatsApp channel in Chat settings using Twilio, but when I click Save, I get this error:

An error occurred while working with the account service. For further information, please contact the system administrator.

Details:

• Creatio version: 8.3.1.4498
• WhatsApp provider: Twilio

I have checked the Twilio credentials and phone number format, but the error still appears.

Has anyone faced this issue before?
Is there any missing setup, system setting, or hotfix required for Twilio WhatsApp in Creatio?

Thanks in advance for your help.