2 things i still want answered why liz never got a grace yet mel got a commandment? an "EARTH" grace would work well for liz .
Because there are only 4 Graces, and Elizabeth isn't really a warrior (she only fights when necessary), giving one to her would be a waste.
and how did a 4 wing angel nanahsi ( arc angel lvl) get banished. maybe he had a grace and lost it in a dual
It is highly unlikely, in fact, practically impossible for Nanashi to have been a former wielder of a "Grace."
According to the Character Guide: Britannia's Heroes Life, the ages of the Archangels are as follows:
Ludociel: 6,000 years old
Sariel and Tarmiel: 5,000 years old
Mael: 3,500 years old
Whioe Nanashi is also 3,500 years old, roughly the same age as Mael, and significantly younger than the others.
He is, in all likelihood, simply an exceptionally gifted and powerful individual within the Clan who disagreed with the SD’s way of doing things (this can be inferred from his thoughts, which Lancelot was able to read). He ended up opposing the SD, which led to his punishment. (After all, the SD even cursed her own daughter, Elizabeth, a curse that caused her to suffer for 3,000 years)