No response after I requested an urgent change in passenger name directly after received the ticket

This is my second message to them; - No response yet Thanks for your e-mail. I must state that I am very disappointed in your service and would probably not use you again depending on the outcome of this mail I expected that when I see a mistake on the booking and I immediately send a message as you requested, to your urgent mailbox that the issue will be addressed immediately as understood from your email (attached) and the paragraph quoted below*** and not after the booking has taken place with the airline. From now till February for when this flight was booked surely you had enough time to wait and see if the particulars are correct. Your response only waited till the next morning when it was too late!

*** ”Please take a minute to verify all your details, especially the passenger names and travel dates as once your ticket has been issued airline penalties may apply to make changes. If any of the information you have supp**** is incorrect please contact us immediately at ********** or ***”

And then your response was equivalent to “sorry this is your problem” “You must contact the airline yourself and request the changes.” In your response you also supp**** me with an incorrect airline number to contact them. This number was for freight only. When I finally reached Qantas they told me that it is the agent’s responsibility to make the corrections. I then phoned Travelstart and the lady, Sharon, explained that there will be a cost involved and she will get a quote from the airlines and get back to me. Unfortunately I have no proof of this, and whether it has been done. This is unacceptable. If the company waited for a response from the client and then submitted the booking there would have been no problem. I have not yet received the quote from you and I am wondering if this is going to cost me more money and grief. I expect Travelstart to carry the cost of this poor service.

The correction on the documents is urgently needed for a Visa application which will be rejected if I try to use the documents you sent me. Who can I contact to fix this?