Xbee S2 with one coordinator and two router , misses the data in-between

I am using 3 xbee S2B modules. One as coordinator and two as router,I have changed the PAN ID on all of these modules to 26. Detination adress on coordinator is 0FFFF and destination address on router is coordinator’s MAC address.
Router xbee connected with Arduino and sends Sensor information to coordinator connected on Raspberry Pi. I do not sens any data from coordinator to any of the router.
Now issue is i miss lot of information on coordinator, sometime i receive data and sometime not.It misses lots of packet. Is it the issue of sleeping Coordinator/router. How can i share the configuration file here.
Kindly help

Routers don’t sleep. If you have a Sleep mode enabled on your router, then it is an End device. If it is an End device, then you must use Hardware flow control to keep from over flowing the radios buffers. You also need to reduce the amount of data being sent from the Coordinator or Parent as a Sleeping End device Must poll the parent for data. The parent can also only hold either 2 packet or up to 120 bytes up to two times the sleep cycle or until the end device polls it.

Broadcast packets the buffer can only hold one for two times the SP time frame.

can you elaborate how to poll for data in sleep mode?