NuEra Telecom I was cheated. Got charged for more than what is supposed to be. Internet

I am a international student in Canada. NuEra telecom has contacted me from their India's office and told me about their $5.00 India calling service. The person told me that its usually $25.00 but they are giving discounts and they are the billing department. If anything more is charged, they will refund. I subscribed for it. I got confirmation calls from US twice where they mentioned about $25.00.

 I contacted the person from billing department again and he said that is just for confirmation. However, I will only be charged $5.00. When I check by credit cards statement I was charged $25.00. I called the person from India again and he told me that a refund will be processed. Then for 3 months continuously I was charged $25.00 and the person did not refund me anything.

Then when I tried to contact him, he stopped lifting my call. I called the customer service people, which is somewhere in Philippines or I don't know where, they refused to give me any refunds and said since I am using the service they cannot refund me anything.

I asked for a Manager and they said they will file a complaint and a manager will call me. I asked to cancel my service and that was done immediately. Afterwards nobody called me. I felt cheated. These people are frauds.

The amount they charged is big amount for me as I am a international student here. I request someone to please help me with this. If needed, I can provide the contact number of the person who contacted me for the service from India.