Error at checkout using Stripe

I am using Stripe for my gateway. Everything was set up and working great in test mode but it does not work in live mode. In live mode I get this error after clicking “Place Order” with a credit card. “No such customer: cus_GjV2r…lOE; a similar object exists in test mode, but a live mode key was used to make this request”. I contacted Stripe and they had me delete the test customer and change the email address of the live customer. Here is more of what they said at Stripe:”Basically, whenever we get this error, we need to make sure that we create a customer object in live mode. If it already exists, please make sure that you’re using the correct customer ID. That being said, this would be something that needs to be done on the integration side. I would suggest that you get in touch with WooCommerce regarding this matter”. I do not understand the part about using the customer id or the similar object that exists in test mode. Is there something stuck in my database that I need to manually clear? I don’t get this at all. any advice will be greatly appreciated.

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