Matrix is not quasi-triangular

Hi All. Dynare presents the following mistake information when I run the model

[code]At …/…/…/…/dynare++/sylv/cc/QuasiTriangular.cpp:128:Matrix is not quasi-triangular

Error using mexErrCheck (line 41)
Error encountered in: gensylv.

Error in dyn_second_order_solver (line 116)
mexErrCheck(‘gensylv’, err);

Error in stochastic_solvers (line 225)
dr = dyn_second_order_solver(jacobia_,hessian1,dr,M_,…

Error in resol (line 137)
[dr,info] = stochastic_solvers(dr,check_flag,M,options,oo);

Error in stoch_simul (line 88)
[oo_.dr,info,M_,options_,oo_] = resol(0,M_,options_,oo_);

Error in V2 (line 980)[/code]
Could anyone know how to solve it? The code is as attched.
V2.mod (10.1 KB)

Run model_diagnostics. The most important issue is

MODEL_DIAGNOSTICS: The following endogenous variables aren't present at the current period in the model: Ht Hnt

Hi Jpfeifer! Thanks a lot! After revised the mistake, I met another problem. Dynare present the information as follows

stoch_simul:: The simulations conducted for generating IRFs to epsilon_yrow were explosive. stoch_simul:: No IRFs will be displayed. Either reduce the shock size, stoch_simul:: use pruning, or set the approximation order to 1.
I searched in this forum and used the option “pruning”, but I still cannot get the IRFs. Would you please give me some suggestions about this issue? The updated code is attached. Thanks!
V2.mod (10.1 KB)

Your model has a unit root that makes all endogenous variables you want to simulate non-stationary. You need to deal with this first.