Turntable?

Probably the turntable motor has failed. A quick search o the usual suspects for spares suggests only very limited support (to be expected for cheap generic Chinese stuff badged up with store in-house labels).

Given a replacement is likely to be in the order of £30/40 you'd be best off simply getting a replacement (and safest - microwaves can be nasty - even powered off!)

acp
April 2017