Error when switching that does not require payment

Get an error in Woocommerce Subscriptions during checkout (“Error processing checkout. Please try again.”) when a customer is switching their subscription product and does not require payment. I think it’s related to this issue: https://woocommerce.com/feature-request/please-correct-class-wcs-switch-cart-item/. But after an update of Woocommerce Subscriptions it doesn’t seem to be working anymore.

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