Casement Window Operator

We just bought this home. All windows in the house appear to be Andersen. However, we don't think this casement bay window is as it doesn't have any markings. We believe the windows were installed in 1985 when the house was built. The window operators allow us to open the windows. However, we're not able to close them without someone going outside and pushing the window closed. We need to replace the operators for both a right and left window.