AnyBus X Gateway AB7900 unable to exchange data

We have two ethercat loops, each of them contains multiple ethercat slaves. We are trying to exchange data between these 2 ethercat loops by connecting them using AB7900 gateway.
On both ethercat loops,we could see that the gateway is visible as a slave and is in Operation Status (OP)
Unfortunately, we are unable to exchange data between these loops. We tried by disabling and enabling control/status words. Our pdo size is 20 .
The question I have is, are we missing something, that is required to enable the gateway exchange data.

Just as a side note, we also have another ethercat loop which has a Beckhoff PLC and it is able to exchange data between our loop and the PLC loop using another AB7900 gateway. We have verified that the configuration of both these gateways are identical.

Were the slaves added to there respective loops configurations? Do you have a master on each loop? What errors are you seeing in the master?