Having issues with ASUS and CISCO

Hello everyone!

I have an ASUS N-53 dual band router and a CISCO E2500 dual band router than I'm trying to connect.

However they do not seem to be working together.

The configuration goes like this>

INTERNET > ISP MODEM (no router) > CISCO E2500 ROUTER > ASUS N-53 ROUTER

The reasoning behind this setup is that the first router, the CISCO one, has both bands independent from the ASUS, as we have an office at home, and the office uses one SSID while the bedrooms use a secondary SSID, different from the first one. We'd like to keep both SSIDs separated. However after spending the better part of a day setting everything up, the first router, from the modem to the E2500 work well, but the secondary router, which is near the bedrooms, does get the signal, but won't surf the web, or give limited connectivity.

Is there a compatibility issue between these brands? I tried setting the ASUS as router, AP and repeater, and none would work (as all 3 modes are supported), the only one that would accept the configuration is the router mode.

Something to point out is that sometimes the router would throw a conflicting IP issue, but that hasn't stopped our laptops from connection to the web and navigate.

We also tried setting both up with static IPs, static DNS, dynamic both, resetting to factory settings, etc.
Have you got any suggestions?

Anything would help.