swings and roundabouts or is it doors and windows?

Today my employer well the HR guy who is mr friendly and often picks me up at drives me to work cma ein to my office looking very concerned. I of course got incredibly worried. He then admitted that due to an error on their part based on an oversight on my part they have not being payii=ng me correctly for a year and a half and I am going to a nice little wodge of backpay. In fact it is a few cents off the exact amount I had to pay in a rent dispute from years ago that finally got 'resolved' recently so its all swings and roundabouts isn't it.
Now if I could just find that important file I lost it would be a great day.