price taken 3r/s higher than printed

Location/place: liluah/ kolkata

Name of company/service: amul milk

Sir,
i m manish kumar, a simple middle class man, i lived at liluah, patua paada, kolkata i used to take amul brand milk, but here in one month price is taken by retailer more than printed price!
That is 3 rupees more than this..
Sir plz help me? Nd do smething?
For dis i must be grateful !
My contact number is dis 9836267063? Help me