I would appreciate it if anyone can help me with this issue, I have changed my priors, however, it does not work. I try to simulate from a multivariate normal distribution based on a given dataset.

The issue is:

```
Chain 1: Rejecting initial value:
Chain 1: Log probability evaluates to log(0), i.e. negative infinity.
Chain 1: Stan can't start sampling from this initial value.
Chain 1: Rejecting initial value:
Chain 1: Log probability evaluates to log(0), i.e. negative infinity
.
.
.
Chain 1: Initialization between (-2, 2) failed after 100 attempts.
Chain 1: Try specifying initial values, reducing ranges of constrained values, or reparameterizing the model.
[1] "Error in sampler$call_sampler(args_list[[i]]) : Initialization failed.
```

and my model is:

```
model<- '
data {
int<lower=0> N;
vector[15] x[N];
}
transformed data {
vector[15] mus = rep_vector(0, 15);
}
parameters {
cholesky_factor_corr[15] chol;
vector<lower=0>[15] sigma;
}
transformed parameters {
matrix[15, 15] chol_cov = diag_pre_multiply(sigma, chol);
}
model {
chol ~ lkj_corr_cholesky(1);
sigma ~ cauchy(0, 5);
x ~ multi_normal_cholesky(mus, chol_cov);
}
generated quantities {
vector[15] x_sim[N];
for(i in 1:N) {
x_sim[i] = multi_normal_cholesky_rng(mus, chol_cov);
}
}
'
```