Need to fix a "All sample times for this block must be discrete."

I'm getting an error with a reference model that I converted from a sub-system. The reference model uses the Comm Simulink library block "CPM Modulation Baseband". The error is " Error using sweep_modulations_mod (line 118) Error in 'Modulator1a/CPM Modulator Baseband': All sample times for this block must be discrete. No continuous or constant sample times are allowed."

Within Modulator1a, I've set the solver parameters: "Solver" to "discrete..." and the "Type" to "fixed-step."