How does one change the date of a project

Hello, I wanted to ask how I could change the release year that appears next to the project title on its main page. What happens is that we created the imdb page in 2016 because it was the original release plan for the short film, but due to a number of factors it could not be released until now. The premiere will now be this 2021. I tried to add it in the realease dates section, but 2016 is still there with the title and 2021 has been added as an extra premiere. We are afraid that this will be a problem for the festival circuit that the short film will start, with premiere restrictions. Could you help me find a way to change it?