Certificate on web Management interface - lte 4506

bbug

Hello !
As I log in on my local router management page at 192.168.1.1

I get a warning that the certificate is not valid for HTTPS.
I see certificate is signed with Zyxel Developement (?) or something like that.
What do I do with this ? I believe I have the latest (final?) firmware.

Thanks !
Cheers Dag