Payroll Professional's Inc

I received pay checks from payroll professionals for 3 years. My employer called in the Hours but they logged them wrong on paychecks. They shorted me thousands of dollars in Overtime pay. I have all of my pay stubs. I wanted them to check their records I have called them but they threaten me with harassment charges for asking a question. Her name was Dorine or something. It is weird I just want what Im owed. Please if you received checks from payroll professionals check them. Check ever pay stub.