JMeter uses reportgenerator.properties file for HTML report related configuration.
Official documentation recommends not to change the content in reportgenerator.properties file. It suggest user to copy the properties to be changed into user.property file and provide required values.
Following could be used to generate HTML report at the end of the testing
jmeter.bat -n -t C:\Users\vingale\Desktop\Jmeter\apache-jmeter-5.0\Writeback\Iconductor_Writeback_With_Configurationbck_Property.jmx -l "C:\Users\vingale\Desktop\Jmeter\apache-jmeter-5.0\Writeback\output\result2.csv" -e -o "C:\Users\vingale\Desktop\Jmeter\apache-jmeter-5.0\Writeback\output\html" -q user.properties
You will have to ensure the report output directory is empty.You will have to manually clear-out the directory or ask JMeter to delete the content forcefully with -f option
-f, --forceDeleteResultFile
force delete existing results files and web report folder if
present before starting the test