Is the YouTube app on your Kodi not working well? Did you try uninstalling and reinstalling the app but it's still the same? So i'll explain another way that might work. Below there's a video of me doing the procedure. The video is spoken in portuguese, but you can enable the subtitles as i've put the english language there.
But i will describe here also in a brief way:
-Instead of uninstalling the app, you are going to remove the plugin. It worked for me.
-Go to System> File Manager> Profile directory> addon_data and choose the Youtube plugin.
-In your television remote or other thing that you use, press the options button, choose Delete and confirm that choice.
-Go back to the home menu and open YouTube as you usually do. An alert will appear saying that it will perform the installation. Confirm this.
-Then choose the Language and Region.
-The app is installed. Now you need to set up your account.
-Choose the Sign In option. There will be a message saying that you will have to enable 2 applications for Youtube to work. This means that you need to have YouTube in a second place, like your smartphone, computer or other device. To connect it, you just go to youtube.com/activate and enter the code that Kodi gives you.
-In your device, go to youtube.com/activate, choose the Youtube account that you want to associate (if you have many), enter the code and accept the permission for the Youtube application to use your account. Usually Kodi asks you to do the same thing a second time. So do it.
That's it. All the menus are back and Youtube is working.
Now, here's the video: