How to find, create and maintain Account Hierarchy

Hi Experts,

could anyone be so kind and explain me how to retrieve, create and maintain "Business Partner Hierarchies" of a customer/Account?

My goal is to replace the standard attribute/field "Parent Account" for an "Custom Extension Field".

Once the user enters an account on this extension field (Custom OVS), I need to recreate the same logic behind the standard field "Parent Account".

My first thought/approach was to understand how the hierarchy can be retrieved/manipulated.

I tried this by performing a Retrieve but I get an empty result:

var BPHierInstance = BusinessObject::BusinessPartnerHierarchy.Retrieve( this.ToParent.UUID );

where "this.ToParent.UUID" = "Customer UUID".

thanks in advance,

kind regards,

Andres