Auto Registration requires a dedicated Product Definition used only for Auto Registration. You cannot use the same Product Definition for both Bulk Registration and Auto Registration.
Make sure you have created a Product Definition first.
Use the Registrations page at https://remote.it to create a new Auto Registration.
Click on “Create Auto Registration”:
Fill out the displayed “New Auto Registration” form.
Add a name for this Auto Registration that will be meaningful to you, then choose the desired Product Definition from the drop-down list:
Finally, click on “Register”.
You will see your Auto Registration in the table, as shown below.
Click on the indicated "Settings" icon to finalize your Auto Registration.
Select the lower two checkboxes as shown, then click on “Submit”.
The status will change to “preregistered”, as shown below.