Cannot getting downlink from server to endnode

I am getting problem, when I am transmitting downlink from (nodered+MQTT) to the end device is not getting at end device. but when one uplink packet received automatically downlink be received at client(end device). i am not able to find where is the problem?
in my observations

  1. In the automatically send downlink packet phypayload contians ACK: true
    ack :true
    fPending :false
    classB :false

  2. Downlink packet which is sending by me from nodered + MQTT phypayload contains
    adrAckReq :false
    ack :false
    fPending :false
    classB :false

please suggest me where is the problem(in my Endnode or Server) & tell me answer how can i rectify this problem

Thanks in advance

3 posts were merged into an existing topic: Sending data to lora node with mqtt