Help with two group model

I am trying to make the two-energy-group model by using the "Coefficient Form PDE" module for both the fast group and thermal group. I am having trouble to find the correct solution for the two group neutron fluxes, because the time-dependent study gives results of almost zero, i.e., the trivial solution, the eigenvalue and/or stationary study gives more reasonable solutions with the same initial and boundary conditions. Could anyone please give me some guide and/or look at the attached file for pointing out my mistakes?
Thanks.