I have 2 credit lines (Amazon, and Walmart) as well as 3 credit cards (Capital One, Chase, and Merrick). Right now, anytime a charge is made on any of the accounts, they are paid through my bank once the charge posts. This keeps the accounts active while also assuring I don’t go back into debt. This tactic works as right now, my lowest credit score is 766.
My Capital One card is carried which makes charges while I am out and about (therefore reducing the need to carry cash). The Chase and Merrick Bank cards are used to handle my automatic recurring bills.