During the battle on Scarif, the X-Wings take shots from the Tie Fighters and they are scoring hits on them as if they have no shields. X-Wings are supposed to have shields as their differentiator from the Imperial approach:
The presence of a hyperdrive and deflector shields differentiate the X-wing from the Empire's TIE fighters, emphasizing the importance the Rebels place on pilots surviving their missions. - Rebel Alliance Sourcebook
Additionally, the X-Wings were able to block the first or second shot from a Tie Fighter in the Death Star mission.
Is there a reason why the shields on the X-Wings were not working in that any shot appeared to have the same effect as no shields?