SMTPAUTH not working for my zencart email

Im getting this when I attempt to use smtpauth on my ecommerce platform

Dec 2 11:47:27 server postfix/smtpd[12354]: connect from server.foreveryours.us[45.33.10.132]
Dec 2 11:47:27 server postfix/smtpd[12354]: TLS SNI mail.lakeservers.com from server.foreveryours.us[45.33.10.132] not matched, using default chain
Dec 2 11:47:27 server postfix/smtpd[12354]: SSL_accept error from server.foreveryours.us[45.33.10.132]: 0
Dec 2 11:47:27 server postfix/smtpd[12354]: warning: TLS library problem: error:14094415:SSL routines:ssl3_read_bytes:sslv3 alert certificate expired:s3_pkt.c:1493:SSL alert number 45:
Dec 2 11:47:27 server postfix/smtpd[12354]: lost connection after STARTTLS from server.foreveryours.us[45.33.10.132]
Dec 2 11:47:27 server postfix/smtpd[12354]: disconnect from server.foreveryours.us[45.33.10.132] ehlo=1 starttls=0/1 commands=1/2