RP: Your oldest revolving credit account was opened too recently.
Revolving accounts allow you to carry a balance and your monthly payment will vary, based on the amount of your balance. Your oldest revolving credit account is still too new. A credit file containing older accounts will have a positive impact on your credit score because it demonstrates that you are experienced managing credit.
Don't open more accounts than you actually need. Research shows that new accounts indicate greater risk. Your score will benefit as your accounts get older.