You want to create Account Hierarchy manually, however, you are not able to find the option to do so.
To create an Account Hierarchy such that Account A is the parent of Account B, please follow the steps below:
1. Go to the Customers work center.
2. Go to the Accounts view.Open the Account B.
3. On the Header of the Account, select the button Parent Account.
4. From the value help, choose Account A and save.
Following above steps you can create multiple level Account Hierarchies, as well.
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