How long does Amazon kyc generally take?

The initial Seller Account Verification can take anything from a few days to a few months. My first verification took almost three months.

Just patiently wait and provide Amazon any additional information or documents which they request. For any questions, e-mail seller-verification-enquiry@amazon.co.uk and here is a verification-related help page, which includes answers to all frequently asked questions regarding Seller Account verification:

https://sellercentral.amazon.co.uk/gp/help/help-popup.html/?itemID=201200780