I have to make an adjusting entry for this:

Unearned Service Revenue still Unearned, $800

There is a previous credit balance of 5,300. At first I thought there was no entry, but then when I started to do the income statement the answer I'm suppose to have is not correct with the answer I have. I need help, I've been working on this question since yesterday and I do not get it! Any help or insight would be greatly appreciated thanks!

So the balance is 5,300.

They are telling you it should only be 800.

Therefore, you need to decrease the account by 5,300-800 = 4,500

Dr. Unearned Service Revenue 4,500
Cr. Service Revenue 4,500