Please read these two guide →
6 - Self-signed SSL error on Outlook/Thunderbird - 06 - Email - CyberPanel Community (This may help you solve your issue on sending email through mail client)
Please read these two guide →
6 - Self-signed SSL error on Outlook/Thunderbird - 06 - Email - CyberPanel Community (This may help you solve your issue on sending email through mail client)