Go to Zapier and login with your Zapier account.
Click on Zaps from the menu on left or directly go to your Zaps using this link.
You will see your Crowdfire → Instagram Zap on the right side.
Click on the toggle button to turn off the Zap.
That's it. Now Crowdfire will not directly post to Instagram using Zapier.
If you want to turn on direct post on Instagram using Zapier and Crowdfire then follow the steps mentioned here.