How to get refund for ptrc ?

Dear Sir,

My firm got established in December 2015.My firm had zero employees till 31 March 2016 (Only two directors) .

I got my firm PTRC / PTEC registration in March 2016.

While paying Professional tax, I  selected PTRC while paying professional tax for my pvt ltd firm for prevoius financial year(ending 31 March 2016).

Since firm had zero employees , I was suppose to pay only PTEC but I accedently paid PTRC.

I wanted to pay PTEC for my firm for financial year ending on 31 March 2016.

Kindly let me know w h I can get refurnd for PTRC  Rs 2500/-?

Thanks