I can't send emails on my iPhone 6. My passwords also automatically stops working once a month

Hi, Marcelodesouza.

Thank you for visiting Apple Support Communities.

I understand that you are unable to send mail on your iPhone 6. I would need more information regarding an error messages received and if this issue happens on Wi-Fi or the cellular data network to provide a better answer. However, here is a troubleshooting article that may help with this issue. Be sure to also check with your mail provider for any enabled security features such as two-step verification.

Get help with Mail on iPhone, iPad, and iPod touch

Cheers,

Jason H.