Brakes Sqeak

Ihave a 1999 Dodge cummins 1-ton dually just recently had brakes fixed on the front 1 new rotor and new pads I drove it for 1 day and they started sqeakin really bad so I took it back they said there was a defected pad so they put a new set on I drove it for 2 or 3 days and they started sqeakin really bad too then 5 days later they start sqeakin when I am not even pushin the brake pedal could you please tell me what it could possibly be they want to drive it to find out but would rather them not so please help thank you