The Navy announced that on Thursday the USS Mustin navigated through the South China sea. The problem is that they did not request permission from China and China believes that people need to request permission. The US claims that these are international waters and the navigation had the intention of being peaceful.

Source: https://news.usni.org/2020/05/28/uss-mustin-conducts-fonop-past-paracel-islands-in-south-china-sea