calculation errors when saved FS quotation

Dear Guru:

I have created a FS product in CRM 7.0 webUI with item category BASE_FS_LOAN02. And then I created a FS quotation with this Product.Things were going fine during the creation. However, when I save it, it showed the errors messages as below:

"Item 100: No financing amount was specified

Item 100: Check error prior to call of loan calculation service"

I wonder if this is because of some integration issue with backend system in calculation because have checked all the places in product from CRM but errors still showed? Is there any way to get ride of the errors? Please help.

Thanks