eDreams Fails to Rebook Flexible Flight Ticket

I booked a flexible flight ticket via eDreams with KM Malta Airlines from Malta to Düsseldorf under the booking number 24624221917. The original travel date was 25.02.2026. Because I have to be available next week for a job opportunity, I wanted to change my departure to 18.02.2026, which should be possible with my flex ticket. On 14.02.2026, I contacted eDreams and requested the change of my flight to 18.02.2026. I received an email stating that the change would be processed, but after that, there was no further feedback or confirmation. I waited the whole night for a change confirmation, but nothing arrived. This morning, I tried again to get information and only received an offer from the airline for an upgrade on my flight, but there was no clear confirmation of the date change. I also tried to reach KM Malta Airlines directly by phone, but was not successful. From eDreams, I only received a ticket number for my request, but so far, there has been no concrete answer or solution. I expect eDreams to carry out the rebooking of my flight to 18.02.2026 free of charge, in line with the flex ticket conditions, and to send me a written confirmation as soon as possible so that I can reliably plan my return trip. I also expect transparent and timely communication about the status of my rebooking request. If I do not receive a binding rebooking confirmation by Monday, I will demand a full refund of the ticket price and appropriate compensation from both eDreams and the airline, as I specifically purchased a more expensive flexible ticket and feel that the service promised has not been provided.