Get timestamp from json object as X parameter in a chart

Hello. I am new to node-red and I can't seem to figure out how to make the line chart to take as X parameter the timestamp from the json.
My aplication sends 5 sets of data taken at diferent times ( I take a measurement at moments x ,x+1,x+2 ..) and the send them all with diferent timestamp at the same time at moment x+5.

I use IBM IOT and my json format is :
{"Sensor1":{"t":29.92,"h":48.74,"p":997.82,"l":151.2,"e":403,"T":0,"ts":"1591872762"}}