0052548: Rounding is not properly calculated after applying 3 x 2 discount (different selling from POS2 VS Backoffice)

Description

It is possible finding flows where the rounding after a discount is not properly calculated. Moreover, the same sell have different total amounts comparing doing that sell through POS2 VS doing that sell through Backoffice (check attached images).
For more details, this specific testlink test case can be followed:
https://testlink.openbravo.com/testlink/linkto.php?tprojectPrefix=Communit&item=testcase&id=Communit-14226 [^]

Steps To Reproduce

Precondition:

Log in ERP as Group -Admin-The White Valley Group

Go to Discounts and Promotions window

Create new record

Header tab

Discount type: Buy X pay Y of same product
Name: 3X 2 Bottle
Starting date: 01-01-2012
Included Products: Only those defined
X:3
Y:2
Products tab

Product: Bottle 1L

---

Now, go to Openbravo ERP

Login with valid Username & Password:

Username: Openbravo
Password: openbravo
And change the role to "The White Valley Group Admin"

Go to Sales Management || Transactions || Sales Order

Click Ctrl + D to create new record

And enter below field values,

Organization: Vall Blanca Store
Transaction Document: VBS POS Order
Business Partner: VBS Customer
Partner Address: . .Barcelona, Pau Claris 138 1-1
Price List: The White Valley Group Sale Price List
Payment Method: Cash
Payment Terms: Treinta días
Warehouse: Vall Blanca Store Warehouse
Invoice Terms: Immediate
Click ctrl + s to save the record.

Move to Lines tab

To add new line item, click Ctrl + D and enter the below details

Product: Bottle 1 L
Ordered Quantity: 3
UOM: Unit
Net Unit Price: 7.85
Gross Unit Price: 9.50
Gross List Price: 9.50
Line Net Amount: 23.55
Discount: 0.00
Line Gross Amount: 28.50
Tax: Entregas IVA 21%
Click ctrl + s to save the record.

To complete the sales order click ”Book” button

And confirm the action by clicking the “OK” button

Select line item and navigate to “Discounts and promotions” tab and verify below details

Navigate to Payment Plan tab and verify the below details:

Expected Amount: 19.00 DEFECT: This amount will differ
Outstanding: 19.00 DEFECT: This amount will differ

Issue History
Date Modified	Username	Field	Change
2023-05-24 11:19	lorenzofidalgo	New Issue
2023-05-24 11:19	lorenzofidalgo	Assigned To	=> Triage Omni OMS
2023-05-24 11:19	lorenzofidalgo	File Added: RoundingProblem.png
2023-05-24 11:19	lorenzofidalgo	Modules	=> Core
2023-05-24 11:19	lorenzofidalgo	Triggers an Emergency Pack	=> No
2023-05-24 11:20	lorenzofidalgo	File Added: DifferentRounding.png

Relationships [ Relation Graph ] [ Dependency Graph ]

Notes
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