Faulty oven still not delivered according to the online store.

I bought an oven from Makro online on 19 Feb 2024. It arrived a few days later. We used it 4 times, and then is was not working. I immediately wanted to log a return, because is was within 7 days. I could not do it, because it is still at Makro and not ever at the couriers. Today it is still at Makro. I sent emails to Makro and Hisense and only received a reply after a month. Last week Hisense sent a contractor to have a look and they saw it was not working, but was not able to fix it. The next day I received a text message from Hisense stating that the repair has been completed. I bought another oven and want to return this faulty one. How can I do that?