Answer

The 12th Tirthankar is Bhagwan Vasupujya Swami.

His Moksha Kalyanak place is Champapuri.

Explanation

Bhagwan Vasupujya Swami attained moksha at Champapuri, which is an important Jain Tirth connected with His life.

Takeaway

So, the moksha place of the 12th Tirthankar, Bhagwan Vasupujya Swami, is Champapuri.