An unknown exception from the MEX file.. While Running FIL(FPGA in Loop)

I am Running Finite state machine counter in simulink FIL using Microchip Polarfire Eval Kit MPF300T. While running the FIL after loading the Bitstream to FIL model, I am getting this error -

An error occured during simulation and the simulation was terminated

Caused by:

Error in "gm_FSM_fil/FSM_fil' while executing C MEX S-function 'filsfun', (mdlOutputs), at time 0.0

Unexpected Unknown Exception from the MEX file...

How do we reolve this issue??

Thanks