Cellc is the worst cellphone contract ever. I regret buying contract phone with them

Cellc is the worst cellphone company ever. If you take our a cellphone contract with them you will owe them forever. I paid them in full but on my credit score it still showing that I owe them hence my credit score is low. I called them, they sent me a paid up letter but they still won't clear with the credit burea. No matter how desperate you are don't take cellphone contract with cellc if you wanna keep your good name