Ensemble is not giving back ACK after ENQ and closes with EOT.

Hello Team,

I am currently working with the CD Ruby machine, which is connected through DIGI. When I click on the “Test Link” option on the instrument, I can see the following behavior in Wireshark logs:

Ensemble sends an ACK (06) after receiving ENQ (05), followed by EOT (04) (somewhat like above photo). However, when another ENQ is received, Ensemble does not send an ACK in response. As a result, the instrument displays a failure message.

Also attaching the Ensemble settings:

I am using a TCP service with an inbound adapter configured for the ASTM protocol. Is there a way to configure the system to send an ACK in response to every ENQ? Please let me know if any details is needed