Uplink payload and downlink payload is locked in the Backend?

How to reset uplink payload and download payload as no new upload messages and downlink payload messages are accepted!

When I now send a test transmission from the end node ( myLora.tx(!); //from the jpmeyers lib for the RN2483 ) I get what was last put in the payloads. A new payload upload and download is not exepted and also after I send “tx(!)” again the connection suspends which can be seen in the console. Only when I power cycle the end node I see the exact payload bytes in the payload again and the connection with the network stop again.