RUTX09: Internal modem update failed / Not enough memory in modem filesystem

Hello,

Same as in closed topic: RutX09 cannot update modem firmware - Networking Solutions - Teltonika Community

Modem Update per WebUI is failing, Device Update per WebUI file Upload ok.

BusyBox v1.34.1 (2026-06-23 10:29:52 UTC) built-in shell (ash)

      \___\_        \_    \__\_  \___\_
     |  \_ \\ \_   \_| |\_ / \_ \\/ \__\_|
     | |\_) | | | | \_\_| | | \\\__\_ \\
     |  \_ <| |\_| | |\_| |\_| |\__\_) |
     |\_| \\\_\\\\\_\_,\_|\\\_\_|\\\__\_/|\___\_/


       Teltonika RUTX series 2026

Device: RUTX09
Kernel: 6.6.126
Firmware: RUTX_R_00.07.23.7
Build: a6a80e3d4b
Build date: 2026-06-25 05:28:21

        \~ INTERNAL API USAGE \~

/sbin/api GET /system/device/status
/sbin/api POST /interfaces/config {…}

Docs: https://developers.teltonika-networks.com

root@vs-aussenlager:~# df -h
Filesystem Size Used Available Use% Mounted on
/dev/root 20.8M 20.8M 0 100% /
tmpfs 120.1M 692.0K 119.5M 1% /tmp
/dev/mtdblock15 576.0K 272.0K 304.0K 47% /log
/dev/ubi0_2 83.6M 1.7M 77.6M 2% /overlay
/dev/root 20.8M 20.8M 0 100% /rom/etc
overlay 83.6M 1.7M 77.6M 2% /etc
overlay 83.6M 1.7M 77.6M 2% /usr/local
tmpfs 512.0K 0 512.0K 0% /dev
root@vs-aussenlager:~#

Is there anyway to update the modem firmware?
Without resetting to Factory Reset as Device in located outside.

Thanks and kind regards

Robert