When open folder: Sent I get Internal error occurred

Hello, I install Mutt with Brew & I run Mutt v.2.1.5. Everything is working fine except if I want to open the folder "Sent". I get this message: 'Internal error occurred. Refer to server log for more information'

After doing Mutt -d 2, I notice this error: 'ssl_socket_open: Error loading trusted certificates'

• But the certificate is good for over 2 years.

Any idea about this?

Thank you.