Sales Budget Error when updating the sales amount????

Hi,
I am doing one customisation in Sales Budget.

Sales & Marketing -> Analysis and Reporting->Budgets

Here we are manually give the sales amount to each item then it gets updated.I did one customisation for updating the sales amount.

I added one button name called as ---->Update..

After giving the Quantity , I am going to click the Update button the corresponding sales price updated in Sales Budget.

For example in sales budget i had 10 items like item1,item2..... All items has sales prices in Sales Price table. i gave
Item4 Qty is 1
Item5 Qty is 1
Item6 Qty is 1

Now when i press update then item4 sales price updated in Item1 not in item4.

Item5 sales price updated in Item4 not in item5.
Item6 sales price updated in Item5 not in item6.
Item6 Sales price is not updated.

why the Sales price is updated in item1.

How can i resolve this issue????


Thanks & Regards,
Kishore.