You’re right, the price for the new plan does look a lot higher. Generally, questions around billing issues are best sent straight to the Support Team as we can’t see your account/plan details here in the Community.
It looks like you’ve already reached out to our Support team who have sent a reply to you on this! It seems that you’re on an old plan that is being phased out and are being moved to a newer plan that would cover your current workflows. If you have any follow up questions I’d recommend continuing the conversation with them over email as they’ll be better able to advise on this.
Sometimes their emails can end up in a spam/junk folder so if you’ve not found their reply it’s worth checking your spam/junk folder, or search your whole inbox for emails from zapier.com.