Sleep mode using OTAA method and LoRaWAN example

Hi guys,

I tried to enable the DEEP SLEEP mode in LoRaWAN simple send example combined Low power sketch and other examples where this mode is set. Using the ABP method everything works properly, but I have some problems when I use OTAA because the device is not able to send the packet and it always tries to retry. Please, do you maybe guys know what could be a problem and reason for that?

Thanks in advance and nice day.