Flight Network services a Sham - Dont use them book direct

This travel company is the worst I booked a flight to Greece Athens via tureky In december through them and i realised I wanted to sleep over a day in turkey to do the tour and I contacted them 2nd week of January via their chat to change my flight details and they are still not coming back to me, the number they have on the system just rings the other one says number does not exist, they dont even have a direct email to respond to am not even sure how to put them on Hello Peter the response to my email was via a no response email service