Smartthings app (from classic) migration / Schlage question

Welcome back. To follow up on what jkp mentioned, you may want to look at this device handler. ST does not officially support programming the Schlage connect locks due to a bug in their firmware which was causing issues for many users. We have put together a patch in the device handler to workaround some of those bugs. See this topic for more details:

As for programming locks you can continue using smart locks with the above device handler or check out the LUM app which offers a lot more than smart locks: