How to keep getting data from analog sensor that was coming during Void setup

Hello, I am currently working on a PCR Thermocycler and wanted to know how to keep attaining data that was coming during void setup keep coming as it is in Void loop. There is a discontinuation in the data when void setup ends and void loop starts. I am attaching the image of data retrieved from Thermistor.
I hope I am making sense and any help in this matter will be highly appreciated.

It's your code, or your wiring.

It's the data I am getting from Thermistor the reading coming in black is during Void Setup while the Data coming in Red in during Void Loop

Yip, it's your code then.