Data type conversion fail in simulink and need to be turn ON

Hello, as shown below that the Data Type Conversion block doesn't function which leads to an error.

While reviewing system message, this is suspecious. It seems to me that this disable the data type conversion. So my question is: how to avoid the data type override by Simulink.

Answer 1

[Hong]

The suggestion from Diagnostic may be misleading. Maybe this has nothing to do with fixed-point tool. This is because that when opening the fixed-point tool, it shows this: It is Off. Therefore, logically, it is hard to believe that fixed-point tool is ON.