Sometimes when I correct fingerings for chords, the fingerings don’t follow the normal sequence from bottom to top using the pop-over and separating the numbers with commas like “2,3,4”. As the video shows the fingerings are associated with the wrong notes.
I have found a workaround: Selecting both voices for the troublesome beat, and using “Swab voice contents” twice will correct the chord.
Link to a video that shows the problem:
I’ve not been able to reproduce this problem based on your video. As a reminder, it’s always easier to reproduce (and potentially fix) a problem if you attach an actual project rather than a picture or video of one. I’ve typed the music shown in the video in to a project and when I assign left-hand fingering by typing e.g. L1,2,4 into the Shift+F popover, everything works as I would expect. Please attach a cut-down project file that reproduces the problem so we can see it in situ.