Casting Devices Don't Show Up On Win 10

Hey! I'm running Win 10 on a HP Pavilion Notebook - 14-ab105la.

My casting devices (Chromecast and Apple TV) aren't detected consistently by the computer, but only randomly every once in a while, and there's nothing I can do to make it work.
Whether it works or not seems to be totally random. (I really doubt it actually is; probably just haven't been able to figure out the cause yet)

Other devices, such as iPhone and iPad DO detect both, Apple TV and Chromecast, at the same time the computer does not.

I'm using AirFlow App and Videostream on Chrome to cast to the devices.

At some point I ran this security scan (https://www.speedguide.net/port.php?port=5353) on port 5353.
After that (hopefully not coincidentially), both Apple TV and CC were detected for a little while, but then I rebooted the system and the issue was still there, couldn't make it work again.

I'm thinking that maybe there's a network configuration problem or something else interfering with that port and/or DNS/Multicast function.

I've already contacted AirFlow App, Microsoft and HP support and none could diagnose the issue.
I hope you can help me out, it's driving me crazy not to, at least, understand what's causing this problem.
Hopefully we can fix it soon.

Thx in advance