Assuming Purchase Orders for Adagio.

Go to Maintain menu drop down, select Tax Groups, and when you select the Jurisdiction, the GL Accounts will be displayed.

Assuming you configured the tax groups properly, the account will be displayed depending on the costing method. If costing method for GST jurisdiction is None, then the recoverable GST is being allocated incorrectly and directly to the inventory or expense. For GST the costing method should be Accounts Payable.

Assuming you have configured correctly, then the GST is allocated to the fiscal period by the Invoice/Adjustment date, and posted to the GL after the POA End of Day is run and the affected AP invoices have been posted in Accounts Payable, and the AP batch has been retrieved into the GL.
Brian