Zapier's paid plans charge a monthly subscription fee. If you received a charge on your credit card from Zapier, either you or someone on your team has signed up for one of a paid Zapier plan.
If you're not sure who signed up for a Zapier account, check in with your team. Typically, a Zapier account is created by someone on your support, marketing, or engineering teams, but it may also be created by a team member trying to connect apps your company uses.
If you can't identify the user that signed up for Zapier, contact Zapier support and the team can help with looking up the email address associated with the Zapier account.