It can be a good idea to just use iterator blocks if you're looking for a loop. But if you strictly want the 'If Action' subsystem to repeat, you can achieve similar functionality using feedback and relational logic. A sample model demonstrating this approach might look like the following:
In this setup, the 'If Action' subsystem block is configured to increment the input by 1 at each time step, repeating this process 5 times. Ultimately, the value 6 is output after the execution of the 'else' block. Also, remember to include a 'Unit Delay' block before establishing any feedback connections, as direct feedback is not supported.
Hope this helps!