step function not compatible with RT-BOX

I am implementing my algorithm into the RT-BOX, and I use the step function.

The error message is as follows:

‘The following components use the value of absolute time. This may cause overflow problems when a program runs for an indefinite time:’

I am wondering what is wrong with the step function?

Maybe I have figure out the problem , I have to redefine the total simulation time of the RT-BOX?

change the setting here!