Switching system is not working as intended, unless I use my meter prob whose Negative is on ba3 negative , how can I fix it?
It does not work because the circuit is not applying 0V to inputs, it only applies 5V when button is pressed but it will float when button is released. Floating inputs are bad as they can float at any voltage between logic high or low or halfway which can consume excess current. The input stays charged to 5V until it slowly decays or connecting a multimeter will discharge it to 0V. This can be fixed by putting pull-down resistors to the inputs so they keep the voltage at 0V unless button is pressed.