Poor service by mtn and dsv

I bought wifi router on the 12th of March 2024 at mtn online store then an agent from dsv called me informing me about when the device will be delivered she said to me it will be delivered on the 19th of March I even received an sms stating that i will get my device on the 19th then suddenly on the 19th she called back saying she is sorry to inform me that my device will no longer be delivered on the 19th it will be delivered on the 25th of March then on the 25th of March a courier guy came and he took my finger print and iD together with my proof of address then suddenly he told me that his device is not working he will come back on the 27th of March I waited for him the whole day he didn't arrive when I called dsv to do a follow up they are not answering my calls then still when I call mtn to cancel my order I find an agent after giving him my personal details they dropped my calls 5× mtn doing the same thing