RB: You have too few revolving accounts with high credit limits.
Revolving accounts allow you to carry a balance and your monthly payment will vary, based on the amount of your balance. Having too few accounts with high credit limits is an indicator that you lack available credit. Having higher limits gives you access to credit without seeking new loans or becoming overextended _ which are triggers for higher risk.
Use credit responsibly and always make payments on time with your existing accounts. After a period of successfully managing your accounts, you can seek increases to your credit limit.