If you signed up through Cloudflare Hosting partner's panel option, do the following to remove that connection to the hosting provider:
1. Login to the Cloudflare account that is associated with your signup through the hosting partner.
2. Select the domain from your account list.
3. In the Overview app, go to the Advanced section.
4. Scroll down to Advanced Actions located in the vertical list of links on the right side of the UI
5. Click Remove Site from Cloudflare.
6. Click Confirm.