You can downgrade your plan at any time through the billing page.

When you downgrade from a higher plan to a lower plan, you will be not be billed. The amount for next billing cycle will get updated automatically.

Please remember that your billing date will not change. And when you downgrade, your response count limit gets reduced with respect to the plan you selected. Some premium features will also stop working depending on the plan.

When you downgrade to the Free plan, your account will continue to be in the existing plan, till the end of the billing cycle. The Free plan will become active immediately the day after the end of billing cycle.