Urgent Opencart paypal checkout tweaking required

Dear Freelancer: I have this site [login to view URL] Currently i have enabled Credit or Debit Card (Processed securely by PayPal) & Paypal Standard... both was working fine on user choice either to checkout through credit card or paypal standard Now the issue arises... people can checkout through Credit or Debit Card (Processed securely by PayPal) but when they select paypal standard and checkout .. nothing happens and cant redirect to paypal page.... When i disable Credit or Debit Card (Processed securely by PayPal) then paypal standard works, but when i enable then Credit or Debit Card (Processed securely by PayPal) works and paypal standard dont works!!!!!!!!!!!!!!!!!!!! Can anyone solve this issue right now.... as i have several customers online complaining this to be resolved..... its not a big issue if freelancer have good knowledge with opencart can solve this issue Regards: