Consumer Redressal

We had bought an inverter which dis still in its warranty period.the same is lying with the shopkeeper for over a month without being replaced for the faulty piece, even though promised.the shopkeeper also refuses to answer our calls.we have all necessary proofs and reciepts.we have been following up with him since a month without being heard and all we got to hear innitially are false Promises. Please help us or guide how to go about this.