RTX tiny and radio interrupt of NRF24LE1

Hello to everyone.
I write code for NRF24LE1 using KEIL and rtx tiny. But i have some problems.

When i first create a task and run it, everythink looks good but when i delete it and then created again the task start runs but when call a radio func with radio interrupt never return.

The problem is that i delete the task and then created again maybe but why........;

thanks.