How to dispute a completed job / change review?

How to dispute a completed job / change review?

Hey there,

I recently purchased a 2000 Facebook likes deal with a Level 4 seller on here. All seemed fine and I gave him a positive review, but the next day the number of likes began dropping precipitously, with no signs of stopping. I'm now 300 likes below where I'm supposed to be and they keep going down.

I have two questions:

1. What are my options for challenging an already completed job and how do I get restitution on here?

2. How do I change a submitted review that reads positive but SHOULD read negative?

Thanks for any help or answers. This has been my first gig purchased here and I hoped I was going to have a more favorable time with things purchasing from a seemingly reliable provider.

Thinker