2nd controller synced but buttons ignored

This is related to this question here but I wanted to actually answer the question (it looks forgotten & we have the same issue): https://answers.microsoft.com/en-us/xbox/forum/all/x-box-s-2nd-controller-paired-but-wont-work-as/461247b7-56fe-4056-a6be-0e97179ebbf3

Basically: all controllers & systems are updated. I've noticed the problem on two separate xbox ones.

Symptoms: 1st controller enters Minecraft or Stardew Valley or Vampire Survivors or hidden in plain sight or Unspotable or any other couch co-op game. They jump into game where a 2nd controller needs to turn on, log in and join the game. It's synced to Xbox. The middle button pulls up the dash board & confirms that they are signed in. But the game doesn't register any other button inputs. No button presses or anything fixes the problem. Closing game and starting it back up doesn't always fix the issue. And on Minecraft, the load times are 5 to 10mins. This turns into inciting wife/husband/child rage.

Latest game is Stardew Valley. It seems like allowing host player to log into game first. Then turning on 2nd controller with a pre signed in account for the controller helps. But the game must have been 100% closed & console rebooted 1st.

Symptom 2: when this issue occurs. I found connecting a 3rd controller only confuses us more. We have a family of 4 & sometimes Adding the next controller allows the next player to join under the 2nd intended players account somehow even though the center button dashboard says the other. I've had to connect 5 controllers before to get it to allow us to play. But the extra controller must remain on or it'll say disconnected. I'm not sure what's causing the issue here. Been using Xbox doe years & never seen this issue until the last 6 months.

Anyone know how to fix this?

:)