Hi Ramy,
If you can still access NWA -> Authentication -> Properties, you can simply reset it to default, which is /logon_ui_resources
If you are unable to access NWA, you can change it via configtool -> services -> com.sap.security.core.ume.service -> ume.logon.application.ui_resources_alias
If I misunderstood your issue please elaborate.
BR, Tom