Error: Unable to access jarfile /picard.jar while indexing the sample for GATK

[SamahElmahdi]

while building bam index, this error shown.
this link was helpfull; http://seqanswers.com/forums/showthread.php?t=62872
i tried : java -Xmx2g -jar $picard_path/picard.jar BuildBamIndex VALIDATION_STRINGENCY=LENIENT INPUT=SRR5858162.dedup.bam # error
then i tried : java -Xmx2g -jar CONDA_PREFIX/share/picard-/picard.jar BuildBamIndex VALIDATION_STRINGENCY=LENIENT INPUT=SRR5858162.dedup.bam # the same error
then i tried to run this code again , picard_path=$CONDA_PREFIX/share/picard- ## 2.21.7-0
then the first code run correctly without error.