I started with a $1,500 SL in June of last year. Used my card for everything from a Starbucks coffee,Best Buy small purchases,gas,groceries etc....kept a small balance on card from month to month. Small increases from $200 to $500 then to 4,200 in October then 6,300 in November then tried 2 days ago, got the 2 day message logged on today and was increased again to 9,500😃. I'm guessing they like the activity and keeping small running balance. Just my two cents. Your CL will also grow before you know it.👍🏻