FWA505 - can't connect more than 32 devices

I have separated 2.4ghz and 5ghz wifis SSID. In total it's not possible for me to connect more than 32 devices for both frequencies. What is the true limit of devices for that model?

Edit:

I just found similar topic:

https://community.zyxel.com/en/discussion/30710/fwa505-max-clients-32-instead-64

Thank you.