Read your report carefully to make sure it is accurate and complete. If you do find mistakes, dispute them directly with the credit bureau. They are then required to investigate and make corrections, if necessary. If you believe that mistakes on your report led to the rejection of your application, you can ask the credit bureau to send a corrected copy to the lender. Follow up with the lender to find out if your application can be re-evaluated.
All lenders have different approval standards.
Just because you didn't get a credit card from one issuer doesn't mean you can't get one somewhere else. Try again with another financial institution. Just don't apply for more than four or five cards in a six-month period. If too many companies reviewe your credit report in a short period of time, it can negatively affect your credit profile. If it all goes well, you should receive an approval notice in the mail in 3 to 4 weeks.