If you call the CySysPmSleep() function when the BLESS isn't in sleep or deep sleep mode, then it will cause issues.
Based on the callstack, it looks like the BLESS is waking up or something, and is being prevented from waking up (something wrong with interrupts possibly). If you have global interrupts disabled, then that is probably the cause of the freeze.
Thank you so much!
Your are right,I modified my code and the problem has been solved.