Xbox One X keeps disconnecting from Wifi even after port forwarding

see about connecting the cable hope it works

... on older forums people were having the same issue with a wired connection. ...

Well, disconnects happen for a lot of various reasons. If others get disconnects on a wired connection, the reason for that happening doesn't have to be the same reason for your WiFi disconnects.

But a wired connection is MUCH more easier to troubleshoot that a WiFi connection.

If your connection via ethernet is stable and doesn't disconnect, we only need to focus on your local WiFi.

If you only use WiFi, we can't know if outside interference (e.g. neighbor with WiFi on the same channel, DECT phones, cordless baby monitors, microwave ovens, garage door openers etc.) is causing your disconnects, or if the issue is related to your Internet
provider (i.e. the disconnects also happen when wired).

And the really bad thing about WiFi troubleshooting is, you don't see the interference. If a disconnect happens, you can't know if
your neighbor was just warming up nachos.

Or the parents next door put the baby to bed and turned on the baby monitor. You just see the WiFi disconnect, and you don't know why it would happen at that time.

As for wireless disconnects: Just recently someone had the issue, that when they connect their Xbox to their TV, everything works fine, but connected to a Soundbar, the WiFi wouldn't work at all. The reason was a ground loop that introduced so much interference,
that the WiFi signal couldn't be transmitted.

So by all means: Try a wired connection, and troubleshoot that at first. If the wired connection works, we can work on WiFi later.

NAT and port forwarding have nothing to do with the console being connected via WiFi or network cable.

So in order to troubleshoot that issue, try to connect your console via a network cable (just temporarily for testing purposes).

If the console still disconnects, you need to check with your internet provider if they are doing CG-NAT.

If the console works properly with the cable, but disconnects via WiFi, you probably have interference that disconnects your console "inside your home".

Either try a different WiFi channel (setting in your WiFi router), or if no suitable interference-free channel can be found, connect the console with an ethernet cable. If running cable through your house is not possible, try using a home plug adapter like
those from Devolo or similar makers.

Try uninstalling your YouTube app and reset your Xbox with keeping games and apps installed. I know it sounds stupid, but it might help. It happened me when I was on YouTube and Turned off console while watching it. I was like 8 hours without connection.
Other devices connected. And then I was like: "ummm, what was the last app I have used?" .... "YouTube!!!!" and it worked =D

It is just disconnects from internet while playing online.