Ensure that you have a stable and reliable internet connection. Weak or intermittent connectivity can disrupt the exchange of encryption keys during a call.
Try ending the call and starting it again. This can sometimes help with the encryption key exchange issues.
Make sure you have the latest version of Telegram installed on your device. You can check for updates on your app store or Google Play Store. Just search for the Telegram app then click the update button.
Make sure that your phone’s time and date settings are correct. Incorrect settings can cause issues with encryption key exchange.
If none of the above steps works, you can contact Telegram support for assistance. They may be able to provide more specific guidance on resolving the issue.
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