I had a similar issue when I moved complete GEDCOMs from Ancestry to Tribal Pages. When I contacted them (TP), they suggested that I use a different browser. I had been using Edge and many entries on the Ancestry tree did not transfer to TP. I switched back to my old stand-by, Internet Explorer, and everything went swimmingly.
Before you go to all the trouble of entering person by person, give that a try.