DATA error unexpected EOF

# Describe the bug

DATA error enexpected EOF when sending email from accesspoint through maddy

# Steps to reproduce

Send email from accesspoint Zyxel NWA210AX via maddy (worked with openbsd/opensmtpd)

Sending from Synology NAS works fine.

# Log files

[hastebin.com](https://www.toptal.com/developers/hastebin/zivecigali)

# Configuration file

only added tls certs and debug + io_debug in smtp+submission / renamed domain / single domain setup

# Environment information

ubuntu 20.04 1 core 2gb ram

* maddy 0.5.4