You could check out the nRF24L01 by using CheckConnection that is in reply #30 of this discussion:
That should give you an indication of whether your radio module is dead or not. If the radio module appears to be working, then try out one of the simple examples in reply #2 or #3 of the same discussion. The code has been proved to work many times.
If the examples work, then the issue lies within your code. But at least you will know your hardware is ok.