My Company Blocked my Salary

Hello All , i am working for a Medical Transcription Company since 4 yrs , i am working here as an Technical Support Executive , I have taken a leave in the current month ( 03/01/2017) as i was sick , My company blocked my December Month Salary and when i asked them for a reason they said it due to the leave i have taken on 03/01/2017 , How can a they block an employee's salary wherein he worked for complete month , when i contacted my HR , he asked me to contact my supervisor , and when i tried to reach my supervisor he is avoiding me stating that he is busy and said he will speak to HR about the same . Now the HR says unless and until my supervisor sends an approval email my salary will be on hold . For our Dept . we do not have any Casual Leaves or Sick Leaves , no matter the situation you are in or you are down with the fever and any other reason , if you take a leave that will considered as Loss of Pay . Loss of Pay is OK , but for one leave they kept my complete month's salary on Hold . Please Advise .