The microwave stops within a few minutes of operation and after a while, it works again.
Check that you cumplied all the installation conditions of the appliance. If the ventilation is not adequate, it is possible to overheat the components of the microwave that force the stop of the same one for safety reasons.
We also recommend to not use high power for long periods of cooking, as this may cause the safety thermostat to activate due to the overheating generated.
Please, check your microwave's installation specifications on user manual.