You cannot use the same API key for multiple websites. If you wish to use our payment system on an additional website, please create a separate website profile for it. Once we approve the new profile, a unique API key will be issued. You can find this key in your Mollie Dashboard under Developers.
This setup makes it easy to keep transactions from different websites separate. You'll be able to view statistics per website profile, which simplifies bookkeeping and accounting.
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