Error in port widths or dimension

Hello,

I'm trying to implement speed control of a dc motor using NARMA-L2 controller. This is a block diagram that I made... I want to check if it'll work... I don't know how

to rectify this error. I did go through the questions and answers already posted on matlab related to this. It hasn't helped me so far. I'd be grateful for some guidance.

Thank you!

This is the model, and I've pasted the error message below that.

Error in port widths or dimensions. Invalid dimension has been specified for output port 1 of 'dcmotorspeedctrl/NARMA-L2 Controller/Zero-Order Hold'.

Component:Simulink | Category:Model error

Error in port widths or dimensions. Input port 1 of 'dcmotorspeedctrl/NARMA-L2 Controller/Control Signal' has 2 elements. This port does not accept the dimensions (or orientation) specified by the input signal.

Component:Simulink | Category:Model error