Omada Controller 5.13.30.20 OC300 crashes while adopting ER8411 v1.0 1.2.1 router. Network is reachable. Please guide what could be wrong. other switches and APs are working fine and connected.

We have three sites with dedicated Omada controllers OC300. How we can use a unified platform to manage all the three sites in single uniform manner. Although, we know that single Omada Oc300 can mana