How do Initiate a Dispute - Freelancer has been logging fake work and charging us

[social]

Freelancer has been logging fake work and charging us  - want to dispute

I already initiated a refund request, but he has gone dark and is unresponsive.

How do I initiate a dispute?  Contract # 28813014

[prestonhunter]

https://support.upwork.com/hc/en-us/articles/211062158-Dispute-an-Agency-or-Freelancer-s-Hours