Writing in the middle of footnote

Hello,

I am writing in a bluebook style. In that style, the year should come last.

However, once I input citation, it is not possible to write in the middle of that inserted citation.

For example, If I make a footnote number 1 such as, "

  1. Rossi, Treaty of Tordesillas Syndrome: Sovereignty ad Absurdum and the South China Sea Arbitration, 50 Cornell Int’l L.J. 231(2017).

"

I want to write 459 in the middle of 231 and (2017) to indicate the actual pages I cited. However, it is not possible. If I write 459, it is automatically erased in a few seconds.

How can I fix it?