Payments Not Paid - Avis employé Writer CopyPress

I still have not been paid for work that was published on client websites 11 months ago. It doesn't matter how many times I write to them, they don't send a check, claiming some internal mixup. When I first started 2 years ago, payments were made quick and jobs were plentiful. One year ago, however, they went downhill and show zero respect toward their writers.