If the error shows 【Linking failed】, you can link Apple ID through your iPhone/iOS device settings.
Open 【Settings】 - 【User Name】 - 【Payment and Delivery】 - 【Add Payment Method】- 【Go to Touch n' Go for Verification】- 【Activate Payment Authorization Service】.
If you have any other issue during this process, please contact Apple Support:
https://getsupport.apple.com/.
If the error shows【Something went wrong】. It might be the network issue, please try again later.