In order to grant access to locked payment methods to individual users please first make sure that the Unlock via User Roles settings is set to Yes on the plugin’s settings page:
With the unlocking strategy active you should now see another field right underneath. On the picture above it’s called User roles with full access to all enabled payment methods. By default all administrators and shop managers have access to locked payment methods but that is something you can change if you’d like by simply removing those roles from the list.
Similarly if you have other user roles that should have unrestricted access to all payment methods just add them to the list and all users belonging to those user roles will be granted access to all locked payment methods automatically.