SSL Error

[Brandon Roa]

I just installed a certificate on my mail server to Postfix and Dovecot. 
The certificate is functional on Postfix, but for some reason I keep 
getting this error. Any suggestions on how to fix it?

mail dovecot: imap-login: Error: SSL: Stacked error: error:1408A10B:SSL 
routines:ssl3_get_client_hello:wrong version number


Here is my configuration:

# 2.2.22 (fe789d2): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.4.13 (7b14904)
# OS: Linux 4.4.0-45-generic x86_64 Ubuntu 16.04.6 LTS ext4
auth_debug = yes
auth_debug_passwords = yes
auth_mechanisms = plain cram-md5 login
auth_verbose = yes
auth_verbose_passwords = plain
base_dir = /var/run/dovecot/
disable_plaintext_auth = no
mail_debug = yes
mail_gid = 5000
mail_location = maildir:/home/vmail/%d/%n
mail_plugins = quota
mail_uid = 5000
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope 
encoded-character vacation subaddress comparator-i;ascii-numeric 
relational regex imap4flags copy include variables body enotify 
environment mailbox date index ihave duplicate mime foreverypart extracttext
namespace inbox {
   inbox = yes
   location =
   mailbox Drafts {
     auto = subscribe
     special_use = \Drafts
   }
   mailbox Junk {
     auto = subscribe
     special_use = \Junk
   }
   mailbox Sent {
     auto = subscribe
     special_use = \Sent
   }
   mailbox "Sent Messages" {
     special_use = \Sent
   }
   mailbox Trash {
     auto = subscribe
     special_use = \Trash
   }
   prefix =
}
passdb {
   args = /etc/dovecot/dovecot-sql.conf.ext
   driver = sql
}
plugin {
   quota_rule = *:storage=5G
   sieve = /etc/dovecot/sieve/default.sieve
   sieve_default = /var/lib/dovecot/sieve/default.sieve
   sieve_dir = ~/sieve
}
postmaster_address = postmaster at example.com
protocols = " imap sieve pop3"
service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0666
     user = postfix
   }
}
ssl_cert = </etc/ssl/certs/example.pem
ssl_key = </etc/ssl/private/example.key
userdb {
   args = uid=5000 gid=5000 home=/home/vmail/%d/%n
   driver = static
}
verbose_ssl = yes
protocol lda {
   mail_plugins = quota sieve
}
protocol imap {
   mail_plugins = quota imap_quota
}