help

I came to Portugal at the beginning of September, the first mobile phone number I applied for was a meo mobile phone number, but the attendant at the shopping mall took advantage of the fact that I didn't understand Portuguese and got me the meo care service without my knowledge, it wasn't until the beginning of October when my bank account was debited that I found out about it and cancelled the service, I complained on the phone, and I was told that I could only cancel the service but could not return the amount that had already been deducted, the I hope meo will return the money I was cheated out of.