Order Information Search Bar - Inconsistent Key Function

Order Info Search Bar
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Inconsistent key function:

Action:
In the MerchantName Search Bar, type a letter "t" to search any Merchant and MerchardID which has a "t".
Actual result:
Currently three merchants are shown in the dropdown list.
Arrow keys on the keyboard works to select the name.
Up Arrow key ? on the keyboard works downward, and Down Arrow key ? on the keyboard works upward in the list of the search resulted names.

Recommendation:

Up Arrow key should work upward and Down Arrow key should work downward.