Hi Web Authentication is not working in ER605 router when its enable I amd unable to access internet also login webpage is not opening (some times its open but very late) but it never opened in iPhone

This may be a question regarding my Er605 router. I have the following setup: er605 4 LANs - 1 home, 1 business, 1 management, 1 guest. DHCP on all LANs except management. Authentication setup: enable