ERROR stack trace Code exception

Hi I am running the RealignerTargetCreator and I am having the next problem:

   INFO  22:02:18,183 HelpFormatter - -------------------------------------------------------------------------------- 
   INFO  22:02:18,207 HelpFormatter - The Genome Analysis Toolkit (GATK) v3.5-0-g36282e4, Compiled      2015/11/25 04:03:56 
   INFO  22:02:18,208 HelpFormatter - Copyright (c) 2010 The Broad Institute 
   INFO  22:02:18,208 HelpFormatter - For support and documentation go to http://www.broadinstitute.org/gatk 
   INFO  22:02:18,213 HelpFormatter - Program Args: -T RealignerTargetCreator -R /LUSTRE/usuario/egonzalez/referencias/Zea_mays.AGPv3.22.dna.genome.fasta -
   I dedup_sorted_JE001.bam -o dedup_sorted_JE001.bam-forIndelRealigner.intervals 
   INFO  22:02:18,226 HelpFormatter - Executing as egonzalez@node48 on Linux 2.6.32-642.el6.x86_64 amd64; Java HotSpot(TM) 64-Bit Server VM 1.8.0_91-b14. 
   INFO  22:02:18,227 HelpFormatter - Date/Time: 2017/02/12 22:02:18 
   INFO  22:02:18,228 HelpFormatter - -------------------------------------------------------------------------------- 
   INFO  22:02:18,229 HelpFormatter - -------------------------------------------------------------------------------- 
   INFO  22:02:19,769 GenomeAnalysisEngine - Strictness is SILENT 
   INFO  22:02:20,252 GenomeAnalysisEngine - Downsampling Settings: Method: BY_SAMPLE, Target   Coverage: 1000 
   INFO  22:02:20,262 SAMDataSource$SAMReaders - Initializing SAMRecords in serial 
   INFO  22:02:20,441 SAMDataSource$SAMReaders - Done initializing BAM readers: total time 0.18 
   INFO  22:02:22,993 GATKRunReport - Uploaded run statistics report to AWS S3 
   ##### ERROR ------------------------------------------------------------------------------------------
   ##### ERROR stack trace 
   java.lang.NullPointerException
at java.util.TreeMap.compare(TreeMap.java:1290)
at java.util.TreeMap.put(TreeMap.java:538)
at java.util.TreeSet.add(TreeSet.java:255)
at org.broadinstitute.gatk.utils.sam.ReadUtils.getSAMFileSamples(ReadUtils.java:70)
at org.broadinstitute.gatk.engine.samples.SampleDBBuilder.addSamplesFromSAMHeader(SampleDBBuilder.java:66)
at org.broadinstitute.gatk.engine.GenomeAnalysisEngine.initializeSampleDB(GenomeAnalysisEngine.java:846)
at org.broadinstitute.gatk.engine.GenomeAnalysisEngine.execute(GenomeAnalysisEngine.java:296)
at org.broadinstitute.gatk.engine.CommandLineExecutable.execute(CommandLineExecutable.java:121)
at org.broadinstitute.gatk.utils.commandline.CommandLineProgram.start(CommandLineProgram.java:248)
at org.broadinstitute.gatk.utils.commandline.CommandLineProgram.start(CommandLineProgram.java:155)
at org.broadinstitute.gatk.engine.CommandLineGATK.main(CommandLineGATK.java:106)
   ##### ERROR ------------------------------------------------------------------------------------------
   ##### ERROR A GATK RUNTIME ERROR has occurred (version 3.5-0-g36282e4):
   ##### ERROR
   ##### ERROR This might be a bug. Please check the documentation guide to see if this is a known problem.
   ##### ERROR If not, please post the error message, with stack trace, to the GATK forum.
   ##### ERROR Visit our website and forum for extensive documentation and answers to 
   ##### ERROR commonly asked questions http://www.broadinstitute.org/gatk
   ##### ERROR
   ##### ERROR MESSAGE: Code exception (see stack trace for error itself)

This is weird because I was running the same code with other data and this doesn't happened before. Do you know what is happening?