The only way to get delinquent credit off of your report would be to make all your payments on time and don't skip any payments, even if given approval.
You must check your credit report. If the delinquencies are still noted, you need to write to each of the major credit reporting bureaus to have your credit report updated.
The drop off point is seven years after last activity, which includes the last payment. If it has been more than seven years, write the credit bureaus to remove it.
Delinquent items automatically fall off seven years from first date of delinquency. Example first date of delinquency is 05/01/2000, it will fall 05/01/2007.