"PaymentOffsiteForm" does not exist [#3346934]

Problem/Motivation

I followed the instructions from the module description. I filled the gateway with the Stripe credentials and tried to complete the checkout, but after submitting the form I got the error "InvalidArgumentException: The class "Drupal\commerce_stripe_klarna\PluginForm\StripeKlarna\PaymentOffsiteForm" does not exist.". Drupal cannot create an instance of the OffsiteForm because the class_exist check returns FALSE. Any ideas how to fix this?

Steps to reproduce

1. Install the module.
2. Fill the gateway with Stripe credentials.
3. Try to complete the order using the "Submit" button.

Comment	File	Size	Author
	commerce_stripe_klarna_error.png	325.44 KB	taraskorpach

Issue fork commerce_stripe_klarna-3346934

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