From version 2.2 our app has built in additional security feature - lock screen whenever app is accessed. In case you leave your phone unlocked and someone is to try to open Salestrekker app they wouldn't be able to open it unless they know to unlock your phone. That way your client data will always remain safe even when you have the remote access.
This is not the option of selection, app is by default set to have this screen. Depending on your phone model and lock screen settings the screen might differ from requesting Face ID, Fingerprint, PIN code or any other option that you may have set in your phone Settings.
To make changes regarding these you would go to your Phone Settings and check and amend security options there.