adirkuhn

Same here,

while we wait for the fix if you are able to edit the plugin files you can check the code of the file
and replace the _fee_amount in the line 221 to _name_percent

payment-method-checkout-fee-for-woocommerce/checkoutfee.php
221        $fee_amount = get_option($method_id . ‘_fee_amount’);
221        $fee_amount = get_option($method_id . ‘_name_percent’);