E750 Mudi freshly unboxed : No Luci

I’m missing the “More Settings” menu item in the GL-iNet Web-Interface and I also can’t access Luci directly via the link 192.168.8.1/cgi-bin/luci .
It simply reverts to 192.168.8.1 .
Firmware is 3.100 compiled on 2019-12-16 15:45:15 (out-of-the-box).
It is very much needed.
Thank you.

Though not E750, perhaps similar issue and solution : Advanced Menu- AR750S - #6 by David

Try if works.

I found it in the documentation: More Settings - GL.iNet Docs
Thanks GL-iNet!