Editing metadata - data lost


OJS is returning blank fields for previously saved/entered fields. One of our editors was trying to update the metadata for some already published articles, and she noticed that if she did not fill out some of the required fields, the data that was already entered was lost. Please see a recording of my screen of this happening at 2019-01-28_1126
In this particular case, the fields that she wanted to update, were not required at the time of the submission, but are now.
We are running OJS