Hi ShortSKorean,
Welcome to Xbox Community Forums. We appreciate for sharing your concern with us and we hope that you are doing well today.
We understand the inconvenience caused. We will be glad to assist you with this. To better understand it correctly, your controller button will not work on Minecraft. As per description, you have tried uninstalling the game, multiple hard resets, and even deleted some old data but still the problem persists. Let us check on this together and sort this out to assist your concern.
For us to provide accurate resolution, we would like to ask more details about it. Kindly provide to us the following information below.
Is this happening on Minecraft only?
When did the issue started?
Have you updated the controller and your device recently?
Check if the in-game button mapping was not change by accident.
For the meantime allow us to recommend the basic troubleshooting to check if this a controller issue seeing it works fine when using it outside of Minecraft. If you already tried the power cycle mentioned above by Parity, then you will need to try out a soft factory reset.
Press the Xbox button to open the guide.
Select System > Settings > System > Console info.
Select Reset console.
Make sure to select "Keep my games & apps" and have your account login information plus your WIFI password ready if you connect wireless because you will need to re-add the account's that were on the Xbox and re-connect to your network during the reset.
We would also like to suggest visiting these articles for more related ideas.
We hope it worked out well for you. If not, please reply back to this forum to let us know.
We will be glad to follow up and help you.
Sincerely,
Geri M.
Xbox Forum Moderator
Microsoft Community