Use to work for a call center which took calls for different companies. One of things they told me was if a department closes which is often since contracts with companies come and go the raises will be remain the same. Base pay can change depending on who you take calls for. My first company left after working at it for 2-3 years and I moved to take calls for another company which I kept my raises. 2 years later they left and I got moved to the same company but different department except that my raises were taken away.
Is that even legal to take away your raises? Plus to make it more frustrating it is a more stressful department and the base pay is 2 dollars less. Safe to say that I left quickly.