Hey!
I would like to disable several users at the same time (because of the Corona lockdown) that I want to let use the lock again later. Is this possible via the API?
Yes. Using
POST /smartlock/{smartlockId}/auth/{id}
with the parameter "enabled": false
This will deactivate the user for later reactivation.
But note though, that you will still have to send all(!) current parameters on disabling/enabling if you want to keep the same settings for restricted access (and not only that one paramater).