无法生成Payload

[doocop]

[-] client (1.1.1.1) read [dialog action: Generate]: null
java.lang.NullPointerException
Exception in thread "dialog action: Generate" java.lang.NullPointerException
        at stagers.GenericHTTPStager.generate(Unknown Source)
        at stagers.Stagers.shellcode(Unknown Source)
        at common.ScListener.getPayloadStager(ScListener.java:197)
        at aggressor.dialogs.PayloadGeneratorDialog.dialogAction(PayloadGeneratorDialog.java:58)
        at dialog.DialogManager$2$1.run(Unknown Source)
        at java.base/java.lang.Thread.run(Thread.java:834)
[-] BEACON_RDLL_SIZE hook returned an unparsable size (null). Valid values (in KB) are: 0, 5, 100
[-] BEACON_RDLL_SIZE hook returned an unparsable size (null). Valid values (in KB) are: 0, 5, 100
[-] client (1.1.1.1) read [dialog action: Generate]: null
java.lang.NullPointerException
Exception in thread "dialog action: Generate" java.lang.NullPointerException
        at stagers.GenericHTTPStager.generate(Unknown Source)
        at stagers.Stagers.shellcode(Unknown Source)
        at common.ScListener.getPayloadStager(ScListener.java:197)
        at aggressor.dialogs.WindowsExecutableDialog.dialogAction(Unknown Source)
        at dialog.DialogManager$2$1.run(Unknown Source)
        at java.base/java.lang.Thread.run(Thread.java:834)

如上报错 请教一下师傅这是什么情况.