How to control COLOR MULTIPLIER by time in Maya


Hello everyone
I am making an animated light switching one in Maya - Vray
but when I set it to :0: for example at 150 fp and 2 at 200 fp
Perhaps it has blended value in animation editor
it either stay on 0 and continue for ever
or stay on 2 and continue for ever not blending

it doesnt change by time WHYYY