Yep, but your LAN (the bridge) has three networks (192.168.3.0, 192.168.88.0 and 192.168.89.0, with the dhcp server on 192.168.88.1), the device connected to the ether2 must be a router (as the 192.168.100.1 is a private address), the device has a dhcp server and the MIkrotik gets the address for ether2 from it, as 192.168.100.2.
I am not sure to understand which kind of device is the airtel at 122.176.152.1 .
Anyway, can you ping from the hap Ac2 the 122.176.152.1?
And what happens with a traceroute to (say) 8.8.8.8?