Dear Kiran,
Akshadeep is right and the relevant provision is written in Sec 73 A of the Finance Act , 1994, reproduced as below:-
(1) Any person who is liable to pay service tax under the provisions of this Chapter or the rules made thereunder, and has collected any amount in excess of the service tax assessed or determined and paid on any taxable service under the provisions of this Chapter or the rules made thereunder from the recipient of taxable service in any manner as representing service tax, shall forthwith pay the amount so collected to the credit of the Central Government.
(2) Where any person who has collected any amount, which is not required to be collected, from any other person, in any manner as representing service tax, such person shall forthwith pay the amount so collected to the credit of the Central Government.
(3) Where any amount is required to be paid to the credit of the Central Government under sub-section (1) or sub-section (2) and the same has not been so paid, the Central Excise Officer shall serve, on the person liable to pay such amount, a notice requiring him to show cause why the said amount, as specified in the notice, should not be paid by him to the credit of the Central Government.
(4) The Central Excise Officer shall, after considering the representation, if any, made by the person on whom the notice is served under sub-section (3), determine the amount due from such person, not being in excess of the amount specified in the notice, and thereupon such person shall pay the amount so determined.
(5) The amount paid to the credit of the Central Government under sub-section (1) or subsection (2) or sub-section (4), shall be adjusted against the service tax payable by the person on finalisation of assessment or any other proceeding for determination of service tax relating to the taxable service referred to in sub-section (1).
(6) Where any surplus amount is left after the adjustment under sub-section (5), such amount shall either be credited to the Consumer Welfare Fund referred to in section 12C of the Central Excise Act, 1944 or, as the case may be, refunded to the person who has borne the incidence of such amount, in accordance with the provisions of section 11B of the said Act and such person may make an application under that section in such cases within six months from the date of the public notice to be issued by the Central Excise Officer for the refund of such surplus amount