Unfortunately, credit scoring is much too complex a calculation for me to tell you specifically what the reason is for you to get turned down for credit (without knowing much, much more about your credit history). I don't want to take a guess, but I am pretty certain that the fact that you are on disability fixed income might have a part to play. I also do not know what kind of credit you applied for, and therefore cannot give you specific instructions for remedy.
Your credit rating is calculated based on several variables, including: your payment history (do you have any late payments, charge-offs, etc.), the amount and type of debt that you owe, if you have maxed out any of your trade lines, and then several other secondary factors like the length of your credit history and how many recent inquiries have been made to look at your credit history.
Generally speaking, all items remain on your credit report for up to 7 years unless you dispute the listing and it is removed as inaccurate by the credit bureaus. A bankruptcy may remain on your credit report for up to 10 years. Most negative listings on your credit report must be removed seven years from the date of account charge off, which usually means seven and a half years from the last time you made a payment.
To my understanding, there is no limit to how long positive listings can appear on your report, but there is really no reason to worry about them unless they are negative and pushing your credit score down.
Here are some steps you can take to help improve your credit rating:
1. Pay off all debts and keep revolving lines below 25% utilization (and certainly don't 'max out' any loans or cards);
2. Get a small store card or gas card and make payments every month (this will help re-establish a track-record of positive payment history);
3. Pull your credit report and contest any inaccurate information so that it can be corrected by the credit bureaus.
To learn more about credit reports and credit scoring, I encourage you to visit the Bills.com Credit Solutions and Resources page.
I hope that the information I have provided helps you Find. Learn. Save.