Posterior mode graph in Dynare (green dashed line)

We know posterior mode is the posterior mode’s distribution curve highest point. Dynare shows this with a dashed green line. But in some cases we can see that this green dashed line does not cross the highest point of posterior distribution curve. My question is that why we see this situation ?
Although in some other cases these is not any problem about the posterior mode graph.

The density is based on actual MCMC draws, while the mode is based on mode-finding. So you may not have found the correct mode initially.

Another explanation is that you may need more iterations in the MCMC.