If you registered it under your iLok user name then it should show up there automatically.
I forget if Serato have that option or if they deposit the license to your account. Either way it should show up on your iLok account. You just plug your iLok in when you log into your iLok accnt and then hit sync or transfer and it should be done.

I understand how to use my iLok.com account.

The problem is the license hasn't been assigned to my iLok account and I don't know how to make that happen:

Here's what it looks like for my two licenses:

Pitch 'n Time Pro 2.5 020460-XXX-XXXX-XXXX Licensed to TurtleRockStudios's iLok
Pitch 'n Time Pro 2.5 1038044-XXXX-XXXX-XXXX

As you can see one is usable, but the other is not.

Hi Turtle Rock Studios,

I apologize for the delay in getting a response, our Support Team has been extremely busy lately.

When you are looking into your products page of your user profile (on Serato.com) have you tried clicking on the "show serial numbers" box? This will prompt you to enter your password, and then your serial numbers should be revealed along with a box which will allow you to enter your iLok ID and send the license to that account.

You may have missed this step when first making the purchase of the license, but the products page is where you will be able to send the licenses to iLok that are not yet assigned to any account.

Here is a direct link to your products page: serato.com

Let me know how you get on :)