go through your dna matches and divide them into groups of the families they belong too. Then look closely at the ones you can't place starting with the strongest (highest cM ) matchesWhen recently researching my family tree I discovered something strange with my paternal grandfathers father. His father, as listed on his birth certificate, died 3 years before he was born (verified both the death and birth dates) so obviously he wasn’t his father lol. So the last name I grew up with, my maiden name, was the dead guys name. But in reality whoever the real father of my great grandfather is, that’s the surname we should have. I always found it odd that in all of my thousands of dna matches on ancestry not one shared my maiden name, but all the other surnames in my family tree are represented among my matches. Now I know why. Id love to know what my “real” last name should be but have no way to know how to go about it. My great-great grandmother is dead so she’s not talking lol.