Sci-fi movie/series about people being mind-controlled

Hi, for this one, I have even less information, it may even be a TV series episode or even from two different episodes.

I watched this when I was in elementary school, so it must be from the 90’s or 2000’s, 2008 max. I have never watched X-Files in that time so I wouldn’t know but when I checked the series a few years back, the tone and atmosphere of not knowing exactly what we’re facing seemed to have been present in the thing I’ve seen. What I’ve seen was a bit gritty, horror-like, mysterious.

I remember two scenes, maybe they aren’t connected.

The first one was something about flies, the flies are indication of a malevolent presence, I remember a character looking at a phone covered in flies and thinking that the threat was close or something.
(I caught the episode out of nowhere on TV and I must have told myself that the flies were because of aliens but maybe I’m wrong)

The second scene was about a group of people being hypnotized or mind-controlled into going somewhere and the children/teenagers seemed to not be affected by it and they can’t pull them out of their trance. And then at one point, the teenagers find the adults waiting inside a yellow school bus itself in a big hangar or garage, and they succeed in moving one adult they trust the most out of trance and then they manage to wake everyone up.
(Again, I must have associated the two scenes and I told myself that they were mind-controlled by aliens but I may be wrong too.)

Thank you in advance for your help.

Black mirror? It is a series, and has episodes where people is mind controlled

Twilight Zone perhaps? There’s several remakes since the original by Rod Serling.

Could it be “Disturbing Behavior”?

Or perhaps “The Puppet Masters”?

There’s an episode of the X-Files about killer bugs

The flies remind me of possibly “miracles”