New Xbox Series X Won’t Control TV Volume

when I had the XBox One I was able to control my tv though Xbox one, but now I have the series x and I cant control my tv though my series x?

So to make this even more confusing to figure out. I just dug out my old xbox one s, fired it up and tested all the controller on
it. The old ones still work fine. The black one that came with the new xbox series x works fine. The new style white controller that come with the new xbox series s and the new style black controller bought today from best buy BOTH have the headset low volume
problem on my old xbox one s. Totally confused at this point.

My controller stop working too series x , factory controller . Last night working and today my samsung tv remote control my xbox and the xbox controller no longuer view by the xbox , i use another controller from my other xbox seris s , and this controller work but not the one work last night , i try the little button to match xbox with but nothing , the controller do no longuer view on my xbox series x , can control de series s but can't be view or connect to the series x anymore

Good news! I got Alexa control working again on the Xbox. Since Alexa sends the signal to the Xbox to turn the volume up/down on the TV, I went to TV control settings in the Xbox settings. Someone had played around with these settings and turned off TV control.
Now Alexa can control the Xbox/TV volume again.

Unfortunately, the problem with the Xbox app connecting to my Xbox continues. Any advice on this would be appreciated! Thank you for the responses so far!

the xbox does not support cec or hdmi control, you would need to go to tv setting on the xbox and setup tv control again as it may have lost the code, the xbox controls tv's via infrared only.

I have this same issue, I just got my Xbox One X, and set up the Xbox to control my TV as well, and the Xbox says it recognizes my TV and is controlling it, and will turn itit onon and off, but when it comes to controlling the volume nothing will happen.