Martin Jonathon Swann, The True King of England. - Dear Geni, How do get my DNA markers linked a Profile

Sweyn I "Forkbeard", king of Denmark, Norway & England

Sweyn I "Forkbeard", king of Denmark, Norway & England

Y DNA markers are only populated so far up the tree. This is due to the amount of variation that can happen over so many generations. Some parts of the Y DNA tree can change within only a few generations, some parts of the tree show no variation over dozens of generations. Since it's not consistent Geni can't auto populate too far up the tree.
Since this profile is ~30 generations from you I doubt even a Y DNA specialist would be comfortable tagging it from one possible result set.