Credit score question

Hello!

There is an item listed on my credit report and has been there for 2 years. Over the past two years I have attempted by phone a couple times leaving voicemails as well as email (for documentation proof) to set up a payment plan for the outstanding balance. I never get a response or a call back. Can I dispute to get this written off or what route what you go? I feel there is nothing else I can do! So bizarre