IF Row has same value in sequence then change row C?

[AndyGray]

Hi Guys, I'm trying to change the value on row C based on Row D sequencing....
Example.

Sold to C1	Business person D1
Plastic Company Index c2	Plastic Company d2
Small Plastic Company c3	Plastic Company d3
Small window firm c4	Plastic Company d4
Small bathroom fitter c4	Plastic Company d5
Flooring Company Index c6	Flooring Company d6
Flooring Company Index c7	Flooring Company d7
Small Floor Company c8	Flooring Company d8
Small Floor Company c9	Flooring Company d9
Trade Person Index c10	Trade Person d10

<tbody>
</tbody>

I need c2 to line up with D 2 3 4 and 5
Then I need C6 to line up with D7 8 and 9
and obviously C10 line up with D 10.

I tried in Cell C2 If D2=D1 Then Display cell C1. if not Display C2.... this never worked. Any suggestions are welcome.

 

[Roderick_E]

build the two lists on a sheet you will hide, then do an index/match to get the result