Minecraft towny bank plots

Hello can someone help me understand and use minecraft towny "Bank Plots"?

On this link: https://github.com/TownyAdvanced/Towny/wiki/How-Towny-Works#plot-types

It explains the plot types and all, but it really doesn’t explain how to use the Bank Plot.

I’ve set a plot’s type as a bank, no residents can place chest as their own bank. Am I understanding this wrong or something? Missing a command?