[faith760]

Prepaid rent still in force $400 but on the trial balance sheet it states prepaid rent 2,700 do I subtract -debit 400 or credit 400

[pready]

Unearned Revenue is a Liability and liabilities have a normal credit balance. Prepaid Rent is a Current Asset and assets have a normal debit balance. When you decrease a liability you debit the account and when you decrease an asset you credit the account.

[pready]

You did not give enough informaation in your problem to determine what to do.

From the information provided by you, you have $400 in Prepaid rent and you paid $2,300 in advance for rent. The journal entry to record this is:
Ebit Prepaid Rent for 2,300
Credit Cash for 2,300

You do not do anything with the $400 until you have used the rent.

Obviously you did not read your problem and did not look at all the information provided in the problem!