Products are not displayed after adding tax and status is changing to "paid" -while creating invoice

I found strange behavior in invoice plane. Here i am mentioning
what i am expected and what actually i am getting. Let me know if i go
wrong.

  1. Click on create invoice and select client ,date and invoice group and then submit. Result- A Invoice record is created with status as “draft”.
    2)Now add multiple products by clicking on “add product”(on top right corner) and submit. Result:- Respective products are displayed in invoice
    3)Now click on “options” and select “Add tax rate”. Select
    "invoice tax rate"(any one) and Tax rate placement as add
    after item tax.Click on Submit.
    Actual Result :-No products were displayed and status is changed to “paid”. and no tax
    rate is included. Invoice is updated topaid with $0 bill.
    Expected: Products will be displayed as in second step and tax rate in
    added at the of invoice and before total amount.Status should be “draft”