Duplicate data after DropDown

[Sewak]

First i select one option from drop down. On the base of that option excel shows relative data.

For example i have different company in one client type, but one of them have multiple staff with multiple contact add.
The problem is how to show only one contact that come first (alphabetically) ..

Please download the attahced excel sheet. I am stocked on sheet 2 (data duplication when i select Commercial Builders.

Thanks