@Amoghh,

I would not think that you would have difficulty with 15 Clients connected to the network, unless they are all trying to communicate at one time. Is there any pattern as to what is causing the devices to disconnect or what devices are disconnecting?

There are a few settings that you could try disabling on your router to see if it will solve the issue:

- Disable Smart Connect - This will Create Two Bands that can have the same SSID

- Disable Fast Roaming - This setting can cause Apple Devices to disconnect or have trouble reconnecting

- For the devices that are disconnecting, try to set a Static IP Address and IP Reservation to see if this is more stable. 

When the Disconnects happen do multiple devices disconnect at one time? What is the Status of the LED Lights when the device is disconnected. If there is no change, you may be able to see the cause of the disconnect in the routers logs.