Simulink Mask won't display parameter values

I want my masked subsystem to display two parameter values, but for some reason it is only displaying the variable name. I am not sure what the problem is. Photos are attached.

Answer 1

[Fangjun Jiang]

1. Variable 'label' is inside the function. It is not visible in the mask workspace.
2. disp(label), not disp('label')
3. Use the following code for "Icon"

Kp=get_param(gcb,"Kp");
Ki=get_param(gcb,"Ki");
str1="Kp="+Kp;
str2="Ki="+Ki;
label=[str1;str2];
disp(label)