Input sources missing
Restart the computer, hold SHIFT before the apple logo show up, this will boot the Mac in safe mode, which will disable all other applications that are not required to start your Mac.  Note that this will take a few minutes. After this, try to locate the Input you need, it should be there.

If that fails, try the fix suggested by Apple.

If this fails, create a new Account.

祝你好运！！ (Good Luck!!)