Incompetence and no accountability by travelstart

Travelstart has been absolutely irresponsible and non - responsive to account for a refund that they are entitled to to credit ! Two payments have been deducted for one flight and the matters was reported within 24 hours ! to amend amd resolve. - numerous emails have been written / statements and the cards have been emailed - with investigation confirmations that the won't b refund - after the duck nd diving - they requests more information which was consequently sent to them with no response ! How does a company realise revenue with no service provided ?charging double the amount for one flight - for same person same day - sure it is quiet logic that based on error this should be credited back to consumer ! It has Been impossible to get hold of them on call - they merely caught a wake up on request sent via twitter ! The maladministration and the incompetence is utterly ridiculous ! As al information has been sent to them Non - refund is unacceptable - he w do you justify retaining money not due to you ??