Hello Hamza,
I understand that you are implementing IMC model in Simulink and encountering error in port width or dimensions. Upon investigating your model, the controller output, which is of single dimension, is being added to the MATLAB function’s block output, which in turn is two dimensional, this is causing the error.
To resolve this, you can simply use a “Demux” block to split the 2-Dimensional signal into two one dimensional signals and then continue with adding the controller’s output to them individually, as shown in the image given below.
I hope this helps.