question

I'm getting the following error while printing receipts using sign on receipt option (my app updates receipt registration provider to add text to the receipt it'll print out, the signature receipt prints, but my receipt doesn't, here's the log:

05-31 15:55:31.855 562-562/? D/PrinterConnector: on service success: ResultStatus{statusCode=OK, statusMessage=null}
05-31 15:55:32.125 562-2124/? W/Seiko: onHandleIntent(PrinterIntentService.java:392): print failed, printer: Printer{uuid=XA99JW5FPC168, type=SEIKO_USB, name=Station, mac=null, ip=null, category=RECEIPT}
                                       java.lang.NullPointerException
                                           at com.clover.engine.services.ReceiptPrinterPlugins.ReceiptGenerator.createReceiptView(ReceiptGenerator.java:2241)
                                           at com.clover.engine.services.ReceiptPrinterPlugins.ReceiptGenerator.createReceiptView(ReceiptGenerator.java:1672)
                                           at com.clover.engine.services.ReceiptPrinterPlugins.seiko.Seiko.printReceipt(Seiko.java:58)
                                           at com.clover.engine.services.PrinterIntentService.onHandleIntent(PrinterIntentService.java:314)
                                           at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:65)
                                           at android.os.Handler.dispatchMessage(Handler.java:99)
                                           at android.os.Looper.loop(Looper.java:137)
                                           at android.os.HandlerThread.run(HandlerThread.java:60)
05-31 15:55:32.165 562-2124/? I/Seiko: scheduleRepeat(PrinterIntentService.java:484): scheduling repeat, delaying 60000ms
05-31 15:55:32.185 562-562/? D/PrinterConnector: on service success: ResultStatus{statusCode=OK, statusMessage=null}

receiptregistrationprovider.updateReceiptAddOnText("my text");

new StaticReceiptPrintJob.Builder().order(order).build().print(context, account);

//clear in 4 seconds, I don't know how to target a specific receipt (in case merchant has auto print customer receipt etc)
Thread.sleep(4000);
receiptregistrationprovider.updateReceiptAddOnText("");