F*ck me, that's a hard one to call, Talip.
They're both woefully mistaken in their own regards, but if I absolutely had to choose I'd say that 'Ghandi' was the more criminally erroneous of the two because it lays claim to being an outright biopic, whereas 'Lincoln' (while insultingly incorrect) is listed as a 'historical drama'.
If you've not seen 'Lincoln' yet, I suggest you overlook my almost predictably scathing review and do so anyway. If you're able to overlook the fact that it's rife with inaccuracies you may find something that borders on enjoyment. Day-Lewiis and Jones' performances alone are worth checking out.
It's more the fact that I'm sick of mythology being touted as history.