Merging two duplicate pages for the same title

Hello, I'm trying to merge two Christmas TV movies into one page - https://www.imdb.com/title/tt38492807/   - link to the page which is the more developed page.  https://www.imdb.com/title/tt38590383  - link to the duplicate page.

But when I fill out the title merge page a red warning appears with this text:

This correction has been rejected. You need to correct this correction before it will be accepted.

• This title correction only seems to change the roman numeral.The destination title you entered does not exist. Changing the roman numeral alone to a title that does not exist does not make sense. If you meant to merge this title with another, use the destination title as it currently exists.

I don't know how I can merge the pages, I don't know if it's because one is classified as a TV special (which is incorrect) and the other as a TV movie.