Hi everybody! I’m currently attempting to implement a ZLB constraint with OCCBIN in a very simple NK model context. However, when I run the code, I encounter the following error message:

“Occbin: Simulation did not converge, increase maxit or check_ahead_periods.”

Can anyone offer some assistance or guidance to resolve this issue?

The code is as follows:

```
var p, x, i, d, s;
varexo u, e;
parameters sigma beta, alpha, lambda, a, b, rhod, rhos;
sigma = 0.5;
beta = 0.99;
alpha = 0.2;
lambda = 0;
a = 0.5 ;
b = 1.5;
phi = 0.1;
rhod = 0.8;
rhos = 0.8 ;
model(linear);
[name='policy rate',bind='ZLB']
i=0;
[name='policy rate',relax='ZLB']
i= a*x + b*p;
x = lambda*x(-1)+(1-lambda)*x(+1) - sigma*(i - p(+1)) + d;
p = beta*(lambda*p(-1)+(1-lambda)*p(+1)) + alpha*x + s;
d = rhod*d(-1) - e ;
s = rhos*s(-1) - u ;
end;
occbin_constraints;
name 'ZLB'; bind i<= 0 ; relax i> 0;
end;
steady;
check;
resid;
shocks(surprise);
var u;
periods 1;
values 0.2;
end;
occbin_setup(simul_periods = 40, simul_check_ahead_periods = 200,simul_maxit = 200);
occbin_solver;
occbin_graph(noconstant) x p i;
```