What color of probe connector is.
We used some 10 golden color connectors, and it is not good.
If the connector is silver color, the connector is very good.
You may need to solder again if still jumping.
You need to push the connector all the way to the end.
You can not calibrate for the first 40 pieces,
Later delivered can be calibrated.
You can press "OK" button and hold for 9 seconds, then use up and down buttons to calibrate.
But before leaving workshop, we had calibrated each piece.
Regarding WIFI operation, please give me how you operate step by step.
We tested each piece before delivery by myself.