set parameter in the Condenser Evaporator (2P-MA) block in app Designer

Hi,

I want to set a particular parameter (number of two-phase fluid tubes ) of the block 'Condenser Evaporator (2P-MA)' from App designer using a discrete knob. I wrote a code, which is similar when I set parameters for other blocks. However, when I run the app designer code and then I set a particular value using the knob, an error message appears in the code: 'Condenser Evaporator (2P-MA) block (mask) does not have a parameter named 'Number of two-phase fluid tubes' (please, see the image).

Do you know why is that happening, considering that the name of the parameter that I want to set is such one? Or such parameter has another name? Does it has to do with the block is masked?

Thanks in advance for your comments...

Regards,

Mauricio