You need to know if your retainage is treated as a reduction of Income or as an Asset. You link it to the type of account that applies for your Accounting requirements. And later, you will Invoice using only the Retainer item. That means:
If this is a Cash Basis entity, the use of the Retainer item (linked to income) negative on the actual sale first reduces Income on that sale; later, it is New income when you charge the customer for it.
Or, as an Accrual Basis entity, the use of the Retainer item (linked to Other Current Asset) negative on the actual sale first creates An Asset that is in lieu of Funds. This is what you have right now = the Retainer is instead of them having to pay All the Money. Money is an asset and you parked some value as Other Current Asset. Then, later, you invoice for the Retainer, which is basically, Moving the retainer amount out of that Other Current Asset to show that now you anticipate actual Funds for it.
Nothing here is wrong, except your understanding of where to see how this info reports. Make sure your entity is Allowed to hold this as Other Current Asset, in the first place.
