Some is put in my family tree incorrectly
I found it like this. I was searching up my grandmother's parents, and found a record already placed for them. Both mom and dad. The only problem is, my grandmother's mother was recorded correctly, while my grandmother's father was recorded as my grandmother's mother's father. I added my grandmother's father into the tree correctly, but since I wasn't the one to put him in the other place INCORRECTLY, I don't seem to have an option to fix it. Please help? I don't know what to do here.