first, please use code fences instead of screen shots: How to use code fences, it will be much easier to read for others
did you install all bindings, actions and persistences that you need? (either in paperUI or in addons.cfg)
can you see a value of your MQTTItem in your sitemap, in other words does it show a value that you expect (if not, your OH2 may not have a connection to your MQTT broker, or your device may not post to MQTT)
you may want to start with a blank rrd4j.cfg, by default all text is commented out, just to exclude that you have trouble with this configuration
you may want to verify your item definition, there seems to be a extra backslash and the word Number at the end may also be deleted, here just for comparison an item definition from my configuration Number Livingroom_temp "Temperature in livingroom [%.1f °C]" (gSensors_temp, gSensors) {mqtt="<[MYMQTT:house/sensornode1:state:JSONPATH($.temperature)]"}