It's not a glaring error but it did seem like he reacted late to it. Think he was expecting the shot to just go over the target but realized the ball was dipping into the top corner and by the time he reacted, it was too late to do anything about it. Maybe if he's a tad taller, he might have saved it and covered that dodgy moment.
And by the way, if people are gonna put the blame on Kepa, then they should do the same on Kante as well. Didn't close Sturridge down well enough. He was on his left foot and we all know he likes to shoot from distance. Kante should have known better.