Blanchard & Kahn conditions are not satisfied: no stable equilibrium & The Jacobian of the static model is singular

I got this error when removing all the bounds and mode_compute=5.

"Log data density [Laplace approximation] is NaN.

Error using chol
Matrix must be positive definite.

Error in posterior_sampler_initialization (line 84)
d = chol(vv);

Error in posterior_sampler (line 60)
posterior_sampler_initialization(TargetFun, xparam1, vv, mh_bounds,dataset_,dataset_info,options_,M_,estim_params_,bayestopt_,oo_);

Error in dynare_estimation_1 (line 471)
posterior_sampler(objective_function,posterior_sampler_options.proposal_distribution,xparam1,posterior_sampler_options,bounds,dataset_,dataset_info,options_,M_,estim_params_,bayestopt_,oo_);

Error in dynare_estimation (line 118)
dynare_estimation_1(var_list,dname);

Error in model.driver (line 806)
oo_recursive_=dynare_estimation(var_list_);

Error in dynare (line 281)
evalin(‘base’,[fname ‘.driver’]);"

I also tried the mode file you provided, didn’t work, same error see picture.

What could possible be the reason for this?