You would request to change the title to: "Uchenitsa Messinga" (2020)
... that is, the exact IMDb-formatted title of the TV series. Include an Explanation such as the following: "This is actually a TV series, not a TV movie. There is already an entry for the TV series in the database, and this entry should be merged into the entry for the TV series."
During the process, you will get two warnings. One will say, "There is a mismatch between the title type of the old and new titles. Are you certain that you wanted to change the type of the title as well as its spelling? ..." The other will say, "The new title already exists in IMDb. Are you sure you wish to merge this title page into this other page for the identically named "Uchenitsa Messinga" (2020)? ..."
Both of those are what you want, so check both boxes marked "Warning understood, go ahead anyway" and proceed. The rest of the process should be reasonably self-explanatory.