SMTP/S interaction does not received on custom ports

[schreddies]

Interactsh version:

version 1.1.5

Current Behavior:

I wasn't able to receive SMTP/S interaction notification on different ports (both udp and tcp). The DNS from SMTP communication notification was received to the interactsh-client, but no communication marked as SMTP.

Expected Behavior:

SMTP communication should be visible on the interactsh-client.

Steps To Reproduce:

I am running AWS EC2 instance, with open security group and aws nlb. The nmap result are :

53/tcp  open  domain
80/tcp  open  http
443/tcp open  https
587/tcp open  submission

running the interactsh-server:

interactsh-server -d <redacted> -ip <nlb> -smtp-port 587 -token <redacted>