Xbee not sending data when wakes up

Whenever i wake up xbee from sleep by deasserting sleep_irq pin , the module doesn’t send data.

Its behaving in quite a weird way that sometime a get the exact data.
While sometime nothing at all.

if i want to get data i need to put xbee to wake up for nearly 8seconds, if i do this there is no point of using sleep mode.

{Why XBEE are so moody} :s

What model of the 900 Pro are you using?

I am experiencing the same issue with a 900 pro XBP9B-DMUT. The nodes are all solid until integrating this transmitter. I do the same all -model running in a sync sleep mode. The transmitter seems to drop the A0,A1, A3, D4 analog inputs values. Other times it is rock solid. Also 900 pro models have worked well.

I have reinstalled the firm XCTU 8071 firmware. Didn’t change a thing.

I am using XBee ZB ZigBee (Series 2), may be the issue with firmware.
Shifting back to series 1 do the trick for me.

What is going on is that the module is in a sleep state for longer than the Sleep period set on the parent node. By doing this, the end device is removed from the Child table of the parent node resulting in the end device having to re-associate. To keep this from occurring, you must set the SP time to longer than the longest sleep time you are going to have your end device sleeping.