Payment methods giving no result

-- HikaShop version -- : Business 3.1.1
-- Joomla version -- : 3.7.2
-- PHP version -- : 7.0.19

Hi there,

We currently have 3 payment methods set up in our Hikashop, and we are having difficulties with all three. Below are the different scenarios we are experiencing:

CommWeb MIGS:
- checkout process works well, until customer clicks 'Finish'. It then refreshes page back to first step of checkout process. Transaction appears as though it was unsuccesful. No error or message of any sort displayed to customer.
- Backend: order displays as 'created' and customer receives 'Your order has been created' email
- No further actions occur after this point.

Paypal (standard):
- When customer enters credit card details in to Paypal, we receive the attached message.
- Backend: order displays as 'created' and customer receives 'Your order has been created' email
- No further actions occur after this point.

Paypal Pro:
- Same customer (front-end) scenario as CommWeb, however no 'created' order appears in backend. It is as if the attempted transaction as never existed; no records or logs anywhere.

We wish to launch our online shop urgently, and need for at least one of the above payment methods to work. CommWeb is our preferred, but at this stage, we would be happy with any.

Once a customer's payment has been received, we require the order status to automatically change from 'created' to 'confirmed' for them to receive their tickets and official confirmation email.

If you require any further information, let me know. We are happy to pay for the services of Hikashop support to help us fix the above.

Thanks in advance.