Payfast and Pre-order plugin

Hi, I am getting at error 400 from Payfast when attempting to pay for a product set up on pre-order with payment billed at a future release date. Payfast error message 400 is “amount, the amount field is required”. Payfast plugin states it works with woocomerce pre-order plugin if when to charge charge “upon release” is selected. Payfast checked settings and ensured correct modules were enabled on my merchant account side, namely subscription and adhoc payments enabled using tokenisation. Payfast recommended reaching out to woocomerce. What am I doing wrong?

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