[Matlab code for DSGE] Invertibility condition violated

Dear Colleagues

I am doing my current work that required me to use Matlab to perform DSGE model ( in economics). I am not expert in writting matlab, thus that cause me lots of problems.

After checking the model, I try to run my code and have the problem:

Error using solab (line 42)

Invertibility condition violated

I checked solab file and see that :

+) rank(z11)=35

+) nk=size(fx,2)=37

However, I do not know which sources cause me this problem, e.g. which functions (f1 to f58).

Does anyone help me to find the sources where I can fix this problem? I checked all equations and make sure there is no typo while typing.