RG801H拨号后提示at port response unexpected ，没有网络

描述问题
提供模组型号、路由器平台、路由器系统发行版等信息
Describe the Issue
Provide module model, router platform, router system distribution, etc.
RG801H，使用usb3.0连接，x86物理机平台，自编译ImmortalWrt 23.05，qmodem版本应该也是最新的，没有next

复现方法
Steps to Reproduce
编译了带qmodem的op，刷进去之后没有调任何设置，能够读取到模组型号RG801，也能显示基站信息，能够正常收发短信，能够拨号（存疑），但是自动生成的2_2网口始终没有ip，也没有数据包

拨号日志：
[2026-06-17 02:15:24] modem_hang:hang up /sys/bus/usb/devices/2-2/ driver ncm
[2026-06-17 02:15:24] modem_hang:ecm_hang
[2026-06-17 02:15:24] modem_hang:auto_dial_hang
[2026-06-17 02:15:24] modem_hang:delete interface 2_2
[2026-06-17 02:15:25] modem_dial:modem_path=/sys/bus/usb/devices/2-2/,driver=ncm,interface=2_2,at_port=/dev/ttyUSB5,using_sim_slot:1,dns_list:,bridge_enabled:0,bridge_port:
[2026-06-17 02:15:30] modem_dial:info sim card is ready
[2026-06-17 02:15:31] modem_dial:create interface 2_2 with proto dhcp and metric 11
[2026-06-17 02:15:31] modem_dial:create interface 2_2v6 with proto dhcpv6 and metric 11
[2026-06-17 02:15:31] modem_dial:set interface 2_2 to eth2
[2026-06-17 02:15:31] modem_dial:network reload
[2026-06-17 02:15:31] modem_dial:firewall reload
[2026-06-17 02:15:31] modem_dial:dialing /sys/bus/usb/devices/2-2/ driver ncm
[2026-06-17 02:15:32] modem_dial:dialing: vendor:quectel; platform:hisilicon; driver:ncm; apn:; command:AT+QNETDEVCTL=1,1,1 pdp_index:1
[2026-06-17 02:15:32] modem_dial:dial_cmd: AT+QNETDEVCTL=1,1,1; cgdcont_cmd: ; ppp_auth_cmd:
[2026-06-17 02:15:41] modem_dial:ip changed from , to ,10.119.61.238
36.8.132.96
29.32.57.162
24.185.161.73
170.150.222.85
[2026-06-17 02:16:36] modem_dial:at port response unexpected

这个模组在win下能够正常拨号和生成rndis网卡上网，功能上应该没问题，但是他会生成很多个端口，有Quectel at port，还有Quectel reserve，Quectel at reserve等等，在qmodem的at调试页面有三个能正常回应at命令的端口，有点怪，猜测可能是把用于别的功能的端口绑定到网口了？不是很了解这个，还望解惑下，感谢

No source file or test is named. Start by reproducing dialing on the RG801H over NCM in ImmortalWrt and inspect the modem_dial logs around /dev/ttyUSB5, the generated 2_2 interface, and the “at port response unexpected” message. Done means identifying whether the selected AT port or another port binding prevents the interface from receiving network traffic.