Microwave not returned since July

Last year around July/August my microwave stopped working & i put in a claim. The microwave was picked up but later i was told the cost to fix it would be equivalent to a new microwave so i said its fine & cancelled the claim. The "microwave" was returned about a month later but it was not the correct & so i told the guy who brought it & he called his superior who promised to locate it & send it asap. 5 months later & they still havent returned my microwave. I had found someone who would fix it but they couldnt because it hasnt been returned. The company that was meant to fix it is at fault but i feel Outsurance is not doing anything about it.