After a reset to factory defaults and re-enable PDP type = IPV4/IPV6:
wwan0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 inet addr:10.138.112.70 P-t-P:10.138.112.70 Mask:255.255.255.255 inet6 addr: 2a02:8440:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx/64 Scope:Global inet6 addr: fe80::b35f:f74b:e9bb:934c/64 Scope:Link UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1 RX packets:169 errors:0 dropped:0 overruns:0 frame:0 TX packets:225 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:41934 (40.9 KiB) TX bytes:24792 (24.2 KiB)
root@lgrrutx:~# gsmctl -p mob1s1a1
10.138.112.70
Idem for %mi the IPv6 part is absent.
Have you tested a configuration where both IPv4 and IPv6 are active ?