Obviously I am missing some important details such as how many systems/ devices are running True Key and which one specifically is the one that you are trying to uninstall True Key to reinstall it afterwards.
This is important, because if you have only one device/system running True Key and you reinstall it, this device will become untrusted and it will be very important to ensure that you know your master password as you would need to authenticate yourself to proceed.
if you know your master password and have access to the authentication step (usually through the email you created your True Key account with), the first thing you should do is to go to True Key settings- export your data to a .CSV file. Once True Key is reinstalled, you can access True Key settings-import to restore backed up file to your newly installed application.
If you require more help, I would suggest you reach out to our technical support team that will be happy to assist you with this: