How do flies catch up with the present if they see the world in slow motion

Flies are said to see everything in slow motion compared to humans (about 4 times slower). If that's true, how do they stay synchronized with real-time events instead of always seeing 'past frames'

Like they have to watch the slow-mo of unnecessary past events, only then can they watch new images

So imagine I'm hitting a fly and it's still seeing the past images

(As dumb as the question sounds to even me, yet i can't figure it out XD)