Receiving a message "The Markdown cannot be greater than the unit price"

When we enter a transaction in the SOP Transaction Entry window we are getting a message, “The Markdown cannot be greater than the unit price”, even though the unit price is actually greater than the Markdown amount. How do we resolve this? On the Pricing Setup window, the “Do not show standard price on initial Item Number entry” is marked. Unmark this option to resolve this issue.