EG-915Q Issue using PPP with TCP

When using a TCP client (Host MCU) with the pppos connection over USB, the TCP connect packet SYN is sent but the SYN+ACK response is lost. I have provided the wireshark capture of both ends in the following image and worked with my IT group to make sure the traffic is sent to the carrier network (AT&T in the case)

Is there some reason that the traffic would be dropped in the modem or by the carrier?

Here is the device and firmware version
image

Hi, bstenquist!

Have you been able to resolve the issue?