Cooktop Wiring Question

That sounds as if it is the case. Do you have the spec sheet on the cooktop? Link us to it if you can, or tell us what the voltage and amperage requirements are.

OK, good. Cap off the white from the wall, connect the red to the white from your cooktop, connect the black to the black to your cooktop and connect the green/grounds. The white was there as a neutral in case the product had a need for 120 volts, such as a clock or lighting. Your cooktop has none, so just use the red and black.