Check the whole process carefully.
Step 1: Get security/authorization code
Make sure the connection between A80 H6 tablet and the vehicle via OBD is proper
Enter “Diagnosis” function

Agree with the disclaimer
Select “Immobilization”-> “Hyundai”-> “Security/Authorization code”-> “47 Authorization Code (smart card)”


Turn the ignition switch off
When security/authorization code is got successfully, go to next step.

Step 2: Program immobiliser/remote
Tap “Program immobilizer/remote”-> “Select from vehicle”-> “General”-> “TUCSON (TL)”-> “2015-2020”-> “Smart key system”-> “Program smart keys”


Turn off the ignition switch
Input security code has got in step 1 manually

Put smart key vertically close to the start button and press start button

Smart key programming is successful, then program next key by the same steps

After the key programming process is done, exit system and check the smart key programmed or not

BTW, attach XTOOL A80 H6 car list for Hyundai (General) IMMO programming.
Note:
Here just share all car models supported in Security/ Authorization code and some car models cover year 2019, 2020 in Immobiliser/Remote system.
For the complete car list, please visit http://www.xtooltech.com/FUNC_DOC/PS_IKHYUNDAI_V27_35_EN.PDF