I followed this information:
1:1 Active/Standby Deployment model:
n this model, the controller in active mode supports up to 100% of its rated capacity of APs, while the other controller in standby mode is idle. If the active controller fails, all APs served by the active controller would failover to the standby controller.
As we have the following setup, this is why I configured dual/dual:
Active/Active Deployment model
In this model, two controllers are deployed in dual mode. Controller one acts as standby for the APs served by controller two, and vice-versa. Each controller in this deployment model supports approximately 50% of its total AP capacity, so if one controller fails, all the APs served by that controller would fail over to the other controller , thereby providing high availability redundancy to all APs in the cluster.