replied on September 30, 2021
It's a little puzzling to me, but here are a couple of directions you might want to investigate.
See if you can find out what, if anything is in that first field. Using the Windows LF client I was able to create an entry in a multi-value field with only a blank space, but when I saved the document an re-opened it, that blank-space field disappeared. I would open the document and put the cursor in both the firstname and lastname field and see if you can highlight any invisible text. If so, copy it out and paste it into a good text editor like Notepad++. If there's anything in there, seeing what it is might provide clues as to how it got there.
I would also study the workflow and any previous processing that affected that document looking for anything that would touch that field.
I realize this isn't an answer, but I hope it's useful.