[Solved]-show two different series with different start intervals with the same xAxis highcharts-Highcharts

It depends on what you want shown on the x axis. If you just want to keep the first axis labels, then simply remove the labels from the second x axis and offset it over the first:

xAxis:[ {type: 'datetime', minRange:31*24 *3600000 , offset:10,
         labels: {formatter: function() {return Highcharts.dateFormat('%e %b', this.value);
        }
    } },
    {type: 'datetime', minRange:31*24 *3600000 , offset:10,
       labels: {enabled:false}
    }],