Want Fill blank cell values with left cell values if condition matches

[amittheexcel]

Hi,

I have below scenario, I want to fill Clean data column with Source data if clean column do not have values only if first column data is matching after source and Clean.

Source_Account_Name	Clean_Account_Name
Amit Chavan	Amit Chavan
Amit Chavan
Amit Chavan A	Amit Chavan A
Amit Chavan A	Amit Chavan A
Amit Chavan
Amit Chavan	Amit Chavan A

<tbody>
</tbody>

 

[Kaper]

What is expected output in : Clean_Account_Name

is it:
Amit Chavan
Amit Chavan
Amit Chavan A
Amit Chavan A

Amit Chavan A

So second row filled with left column, 5th left empty because in first column row 4 and 5 values are different