> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://klassroom.crisp.help/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# How to purchase or input a license key already purchased to upgrade your subscription


### How to purchase or input a license key already purchased to upgrade your subscription

You've received your quotation and license key, but don't know what to do with them? 

To use your license key, enter your class:

- Click on “My Free Offer"

![From the Application](https://storage.crisp.chat/users/helpdesk/website/3cc5342c6be70e00/img7d252518eb9f-1_kcesld.jpeg)


![From klassroom.co/](https://storage.crisp.chat/users/helpdesk/website/3cc5342c6be70e00/capture-decran-2024-08-27-a-12_jgowfx.png)

- Click on “I already have a license key” at the bottom of the window.


![](https://storage.crisp.chat/users/helpdesk/website/3cc5342c6be70e00/img79f98990b2ed-1_urxoyx.jpeg)

- Enter your license key and confirm.

The message on your class has changed and should now mention your offer with the status “Active”.



| If you'd like to start using advanced features today and the school said they were going to cover the costs, you can choose the option "Request my school to pay within 30 days" and they will receive an invoice, so you can enjoy the klasswork and other advanced settings immediately !