Spouses unable to return home due to failed ticket booking: what happened

Couple Emma Giantisko and Dylan Marton spent a lot of time and money due to the contradictions between partner airlines Lufthansa and United Airlines trying to get home after a long trip to Asia. The couple spent two months traveling through Southeast Asia and finally embarked on a long journey home to New Jersey in August.
They booked their flights a month in advance with United Airlines. The route was from Singapore to Munich. The couple successfully made it to Munich, but before they left for New Jersey, the Lufthansa crew informed them that their next flight was canceled due to weather, according to the Business Insider.
It is noted that their tickets were rebooked several times, but the reservation kept disappearing from the Lufthansa and United apps.
After the connection was canceled, the couple thought there would be a new flight the next day. After an uneventful flight from Singapore to Munich, the couple boarded a connecting Lufthansa flight from Munich to New Jersey. According to the couple, they were on the plane for three hours, but a new thunderstorm in Germany caused a delay, and eventually their flight was canceled as well.
Lufthansa told the couple that they had received a free rebooking for the canceled flight. The carrier's representative told them that the next available flight would be in two days, so they agreed to the flight and planned to spend time exploring Munich.
Moreover, the travelers even received confirmation of the new flight via chat, but when they opened their account, there was no indication that they had a reservation for the near future. According to them, this is the first of many such cases.
"We didn't get any tickets, we didn't get any confirmation, and we didn't get anything," said an exasperated Emma Giantisko. The couple says no airline has taken responsibility for their rebooking problems.
The woman said she called United about the missing reservations and was told by an agent that "Lufthansa has taken control of the tickets. There's nothing we can do and your ticket is no longer yours." So they called Lufthansa, but they told them the opposite.
Eventually, a frustrated Marton called Lufthansa back, and Gentisco called United. When both agents told them that it was the other airline's responsibility, the couple put them on speakerphone so that the agents could talk to each other. So the airline representatives started arguing on the speakerphone.
Eventually, after numerous arguments with Lufthansa representatives, the airline rebooked the tickets for the fourth time. But they also disappeared from the online service. The failed flight connection resulted in several rebooking attempts, several lost days, and dozens of fruitless phone calls.
The couple notes that the biggest frustration was that no airline took responsibility. The couple spent $3153.5 on new two tickets that they thought Lufthansa or United could have booked for them for free from the start.
They finally made it to New Jersey, but the saga was not over. After all, their luggage got lost during the flights. The couple said they last saw their luggage in Singapore, and there is still no indication of where it might be.
The couple said they have contacted the airlines to get a refund for all their purchases. The carriers, in turn, promised that they would receive full compensation for flights, hotels, taxis, train rides, meals, and things they bought during the stopover. However, the travelers still doubt that it will be easy.
In total, the couple said they spent $4,430.79 of their own money, including all expenses from purchasing additional tickets, to travel, accommodation, and meals.