LCD Character Error After Activation

Hi All,,

I have a project to control activation of Glow Tester. I want to display with LCD 16x2 to count how much it's activated. but I'm got problem with error display during activation. Anybody know how to fix it?

Glow Tester like I attached,
Spec :

  • Input 220V, Output >15 kV

I control in input with switching relay.

Rgds.

Glow Tester1.png

Glow Tester2.png