alvarodecadiz9 on ThingSpeakException: Update failed

Hello.

I have a problem. When I run my program, at the first iteration I can send the datas to ThingSpeak, but in the second iteration I have the following exception:

com.angryelectron.thingspeak.ThingSpeakException: Update failed.
at com.angryelectron.thingspeak.Channel.update(Channel.java:159)
at clases.CanalThingSpeak.enviarDatos(CanalThingSpeak.java:29)
at clases.Simulador$5.run(Simulador.java:233)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask.runAndReset(Unknown Source)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(Unknown Source)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source

How can I fix this?

The code is in the following link:

Code to send datas to ThingSpeak

Thanks.

Kind regards.