REQUIRED for all errors and issues:
a) GATK version used: 4.2.4.1
b) Exact command used: Mutect2
c) Entire program log: see below

Hi there

I am trying to use the panel of normal for variant calling (I don't have a germline matched for some of my samples) but I am getting repeated error messages and I wonder if this could be a problem with the version of GATK I am using. The command line code and the error message I get below. 

Code:
/share/apps/jdk1.8.0_131/bin/java -jar /share/apps/genomics/gatk-4.2.4.1/gatk-package-4.2.4.1-local.jar Mutect2
-R /SAN/colcc/sarc_amf/0.1.referenceFiles/GRCh38_full_analysis_set_plus_decoy_hla.fa \
-L /SAN/colcc/sarc_amf/0.1.referenceFiles/Twist_Exome_Target_hg38.interval_list \
-I /SAN/medic/EpS/2.0.bamFiles/S00118495/S00118495.mkdub.bam \
--germline-resource /SAN/colcc/sarc_amf/0.1.referenceFiles/af-only-gnomad.hg38.vcf.gz
--panel-of-normals /share/apps/genomics/hg38/1000g_pon.hg38.vcf.gz
-O /SAN/medic/EpS/3.0.variantCalling/3.1.mutect/7342185/7342185.mutectCalls.vcf

/share/apps/jdk1.8.0_131/bin/java -jar /share/apps/genomics/gatk-4.2.4.1/gatk-package-4.2.4.1-local.jar FilterMutectCalls \
-R /SAN/colcc/sarc_amf/0.1.referenceFiles/GRCh38_full_analysis_set_plus_decoy_hla.fa \
-V /SAN/medic/EpS/3.0.variantCalling/3.1.mutect/7342185/7342185.mutectCalls.vcf
-O /SAN/medic/EpS/3.0.variantCalling/3.1.mutect/7342185/7342185.mutectCalls.filt.vcf

Error:
***********************************************************************

A USER ERROR has occurred: Argument output was missing: Argument 'output' is required

***********************************************************************
Set the system property GATK_STACKTRACE_ON_USER_EXCEPTION (--java-options '-DGATK_STACKTRACE_ON_USER_EXCEPTION=true') to print the stack trace.
/opt/gridengine/default/spool/saunders-608-35/job_scripts/4725046: line 18: -O: command not found

Thank you in advance for your help

Simon