Heres what a few have done recently (Dec 2020- early jan 2021).
Step 1) go here and do this
https://support.myharmony.com/en-us/harmony-experience-with-smartthings
It will add a smartapp in your SmartThings system.
Step 2) go into Smartapps in your SmartThings install, then Harmony (Connect) and configure the hub. (you will have to be patient and wait for the hib to load up. It can take a couple minutes)
After step 2 your activities should be listed.