If the two rak'ahs of Duha prayer are considered a charity for the 360 joints in the body, does praying eight rak'ahs of Duha increase the number of charities to 2880, or does it remain 360?

Duha prayer is a great act of worship; its two rak'ahs suffice for 360 charities, as it involves expressing gratitude for Allah's blessings upon all joints of the body. The most complete form of it is eight rak'ahs.