Unfortunately, rehabilitating a credit score is not as easy or as quick as its destruction. While delinquencies account for more than a third of your score, there is hope. Implement the steps in the section "Repairing Negative Information on your Credit Report". While solving old debt problems, stay current on your existing debt to have maximum impact for your effort.
Rapid rescoring is a credit score hack that works super fast, often in just 48 hours, since the credit bureaus prioritize these requests. However, only a lender can initiate this process; you can’t do it yourself. But it is your right to ask for rapid re-scoring when appropriate in order for you to get approved for a home loan or to get the best loan rates and terms available to someone with your credit standing.
If you have missed payments, get current and stay current: the longer you pay your bills on time after being late, the more your FICO Scores should increase. Older credit problems count for less, so poor credit performance won't haunt you forever. The impact of past credit problems on your FICO Scores fades as time passes and as recent good payment patterns show up on your credit report. And good FICO Scores weigh any credit problems against the positive information that says you're managing your credit well.