This past July, my college-age daughter got a $2500 care credit SL for Invisalign (dental work). TWo weeks ago, the card reported to the bureaus (she used up all her CL) her scores dropped from 730s and 740s to 690s so she was disheartened.
I came here here to find advice and we got great results. We called the number on the back of the card. Waited for the automated service to give us a chance to say "credit limit increase." We had read on here that they counteroffer so we asked for a $10,000 CLI. We waited a few seconds and they gave my daughter a $12,500 CLI. That means her new CL is $15,000 and she owes $2,500. When the card reports later this month, she should see a nice bump in her scores.
Thank you, MyFico people, for sharing your advice. You never fail me.