Stripe API not linking

Hi,
I installed this plug in, entered payment details with Stripe, but every time i test it this comes up:Error occurred: No API key provided. (HINT: set your API key using “Stripe::setApiKey(<API-KEY>)”. You can generate API keys from the Stripe web interface. See https://stripe.com/api for details, or email [email protected] if you have any questions.
I’m following the instruction, and I have tested Stripe with woocommerce and I had no issue.
What could be happening? I’m selected the option Stripe SCA suscription.

Thanks

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