3813224 - Why does approver prompt not show when submit Cash advance using expense report?

We have a Cash advance setting using Expense product. Users checked For an approver when an expense report is submitted on Expense Preferences screen.
And checked Allow users to select their own approver for cash advance requests on Cash Advance Settings tab in Workflows screen.
But approver prompt does not show when submit Cash advance. Why approver prompt does not show when submit Cash advance using expense report?

I would like to confirm approver flow prompt when click Submit button for submitting Cash advance. Why approver prompt does not show when submit Cash advance using expense report? , KBA , CON-EXP-CAV , Cash Advance , Problem