Recovery of salary for sanctioned Maternity leave on joining

[Romana]

I had applied for the post of Consultant (Doctor) in ESIC Hospital in 2008 got interviewed in 2009 and was offered job in May 2010.Since I was pregnant and delivery was expected in September 2010 I requested for extension in joining, which was granted for three months and I was asked to join by 14 Aug 2010.Accordingly I joined on 12 August 2010 and applied for ML from 14 August to 13 Feb 2011.The leave was granted and later sanction order also issued by the Medical Superintendent of the Hospital.On my joining back I was paid the salary for the leave period.My probation completion order was also issued in December 2013.
Recently, during audit inspection ,it has been pointed out the no salary was due to me for the period of ML.Although the same has not been intimated to me officially, but unofficially I have come to know that the finance section is working out amount of recovery to be made from me for the salary paid during the ML period.
Kindly let me know if the audit objection is correct and the salary is recoverable from me?If not which rules can I quote/refer to so that I can officially take up the issue with the finance section of the hospital.
Thanks