Cell phone service

I have been a T-Mobile customer for five months. My daughter has had her phone replaced twice due to malfunctioning keys on her Nokia phone. The second time we had it replaced the customer service person said "you are lucky we are replacing the phone". My wife and daughter's phones have had regular SIM card failures during recent months. T-Mobile suggests we replace the SIM cards... $40 our expense. I feel T-Mobile should provide equipment that works or replace it at no charge for the first six months.