Current not stable in Voltage Divider

[ma1990]

Hello! I recently built a voltage divider, and tested out resistors before soldering, which were in good condition. However, when I connect my divider to the HV supply my current seems to be unstable.

The current should read 210microA, but it keeps fluctuating between 218-219 even after 10 minutes of voltage running through it. I have re-tested the resistors still connected to the board with the use of a multimeter and they all still give me their correct value. I even added extra solder support to the resistors thinking that one might be lose but I have had no luck in stabilizing it.
Any suggestions?

I would greatly appreciate it,
ma1990