Answer:
Knowledge
Explanation:
Based on the information provided within the question it seems that David is most likely suffering from a Knowledge Gap. This is a lack of information within a certain topic. Since David does not seem to have the information that customers wanted services like gift cards, return policies, and special orders, he was not able to relay this information to the company in order for them to make an informed decision/change, and was why he was shocked when he found out.
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