CC:Closed by credit grantor ,repair credit question

Hi guys
I have 1 CC showing "Closed by credit grantor", which i owed the bank b4, the date of last activity is 2011-07,
and one showing still under a collector, last payment is 2012-03
I want to know should i start fix my credit score now ? or i should wait until it disappear on my credit report after 6 years count from the last activity date ?

thanks