Often we see complains regarding either of these online so called travel agents. And some might think that if one is bad, another one should be worth a try. Wrong! eDreams, GO Voyages, Opodo and Travellink all belong to the same company: http://www.odigeo.com/. And they are all facing countless number of complaints on the travel forums!
Many of us furthermore wrote it more than once: travellers should never use online third parties and should always book directly with their airline (or with a real travel agent - one with a local office in your city and that is recognised by IATA - for complex itinerary).