Charging more than what was the basic tarrif plan

Location/place: Baroda

Name of company/service: Tata docomo/ Telecom

Please refer my tata docomo mobile no. 7405409700, When i purchased this sim, the call charges were 1ps/second for STD/Local. In last month i recharged with 28 rs to minimize the call charges up to 1paisa/2 second for 30 days and were restricted to 1000 minutes by scheme itself; Now after expiring 30days, the call charges has been changed from original(base tarrif plan at the time of purchasing the SIM) 1ps/second to 1.5ps per second without any request from my sided or information from Tata docomo side. which is really unjust.

in fact, After expiring the validity of any scheme, the old rates should be applicable.

I want justice.