Paypal Checkout Buttons Not Showing on Checkout Page

I’m using a custom theme, and i installed paypal payments for woocommerce, but the paypal buttons won’t show up on the checkout page ,they show up on the cart and single product page but not on the checkout. Also when i click on the Place Order button from woocommerce it gives me the error “No PayPal order found in the current WooCommerce session.”

Can you please assist !
Thank you in advance.