mailcow on Amazon EC2 instance

Hi,

I have tried installing mailcow on an EC2 instance. However, every time the installation is complete the connection to the server closes and it is impossible to SSH into the instance. Also after an instance reboot.

I have tried mailcow guides for adjusting MTU and disabling IPv6. No luck.

I cannot see anything in the server system log explaining the issue.

I might think that it has to do with users getting banned but I cannot even get to look at the ip tables.

Any advices on how to fix this problem will be appreciated :)

Thank you!