Please provide more details like, ZD firmware version, how many APs are connected to ZD, what AP model.
Try to download any free wifi scanner on your Android/iOS or windows system and check if scanner is showing WLANs or not.
"Not in range" is expected when your device saves the WLAN settings but that specific WLAN is not broadcasting or you are far from it.
Most probably its a configuration issue which you may have to check from ZD side. If you are not much familiar, log a support case for assistance.
Below is the user guide for 10.4 (latest version).https://support.ruckuswireless.com/documents/3167-zonedirector-10-4-ga-user-guide
Syamantak Omer | Community moderator | Staff TSE | CWNA | CCNA | RASZA | RICXI | Follow me at https://linkedin.com/in/syamantak-omer-5949b6124