Your cleaner has been fitted with a thermal cut out to protect the vacuum cleaner from damage should it get too hot and overheat. Blockages or dirty filters may cause this to happen, the safety cut off will activate and switch off the electrical supply.
If the cleaner has cut out, simply unplug and check for a blockage or dirty filters. Please look at the advice guides for loss of suction and not picking up dirt, for tips on how to clean the filters fitted to your product. Once all of the checks have been done allow the cleaner to cool down which is usually around 45 minutes. Once its cooled down and plugged back in it should start to work again as the cut out is designed to automatically reset.