Mytrip.com complaint: Insufficient customer problem solving

I used the Momondo search engine to look for flights to Edinburgh Scotland. Having entered dates, destinations, people and baggage needs I found a suitable trip. Choosing the trip took me to MyTrips.com where I proceeded with booking.
On MyTrips I could see that persons, dates and baggage requirements existed but the MyTrips site makes you choose their own specific type of ticket. Thereafter you must choose, insurance, cover for tickets, baggage cover, and baggage. Having chosen baggage in Momondo and I could see that baggage followed the booking I chose to ignore the baggage so as not to pay twice. What happened was that the baggage then mistakenly landed on our home flight but not on the outgoing flight. Seeing this mistake I contacted the company the same day to change this. I was told to re-purchase baggage. According to Norwegien – the company actually handling the flights, MyTrips could have moved our baggage to the correct position but they chose not to. MyTrips platform has carried the details incorrectly and should have informed me correctly of solutions to this booking but chose to make me pay extra.