When a revolving credit card account gets charged off with a remaining balance, the CL that was associated with that card is no longer factored in utilization calculations. Until those accounts are paid to zero, or fall off your reports, they're scored at 100% utilization, and are most often updated monthly, so they will continue to tank your scores heavily.
Although the CO status will continue to suppress your scores the entire time they're on your reports, once you pay off a charged off account and it reports a zero balance, you'll start to see better score improvements as more time passes with no further missteps in your payment history and utilization compared to if they were to remain unpaid and continue to report balances monthly.
I'd first start by getting all your COs paid in full so you can start looking at them in the rear view mirror. Then focus on keeping your utilization down and making on-time payments with all your open accounts. Also look into practicing AZE0, lots of threads here on the subject.
