ZEP application- Proof of payment

Dreadful! Hav done this application a few times for staff. The last three were easy. The most recent one has been a nightmare! Completed the forms for two individuals, submitted CC details. Website indicates payment received and funds were transferred out of my CC instantaneously. Have been calling and sending emails repeatedly to VFS Global with stupid replies... Sent them screenshots of the payment on my CC statement etc. I then received a mail to please download the POP from their payment page by selecting the Payment tab, then the pre payment at bank tab, then the download the bank receipt tab.... It then downloads an HTML attachment, which shows a whole bunch of gargled letters and numbers... I have sent this numerous times and they keep responding to say there is nothing attached.....How much time am I supposed to spend on emails and phone calls with staff who don't even know what a HTML attachment is? And trying to find a contact number of VFS Global in order to speak to someone who has some common sense is impossible! How is this customer satisfaction?