air flight ticket recompensation with reference 5TYMJ55

On the 21 November 2019 I booked my return flight ticket with Computicket reference 5TYMJ55 from Johannesburg to Kisangani (Congo DRC) dated 9 December 2019 via Addis Ababa with Ethiopia airline as service providers flights ET858/ET833 and return from Kisangani (Congo DRC) to Johannesburg dated 29 December 2019 via Addis Ababa with Ethiopia airline as service providers flights ET833/ET809, It turned to a nightmare on the 09 December 2019 when arriving at Johannesburg airport for my flight at about 9pm and my flight time 23h, I was told by the Ethiopian airline that my flight will no longer arrived at Kisangani (DRC) as booked but will only stop at Kinshasa (DRC) I tried to explain to the Ethiopian airline management that I have booked my tickets 3 weeks earlier and my return ticket was confirmed with Ethiopian airline references and times prior's was given, no one called or emailed me or informed me that the flights service booked will no longer reached Kisangani (DRC) as booked but will only stop at Kinshasa (DRC), I was given no other choice beside to be dropped at Kinshasa, arriving at Kinshasa I have to buy another flight ticket myself from Kinshasa (DRC) to Kisangani (DRC) while I did pay a full flight fare from Johannesburg to Kisangani (DRC) already, as a consumer I finds this unfair and I deserve a recompensation for my ticket paid from Kinshasa (DRC) to Kisangani (DRC), my return was okay I did get a flight from Kisangani (DRC) via Addis Abeba to Johannesburg as booked dated 29 December 2019 with Ethiopian airline as service provider.