If there are expenses that have been submitted, and you would like to remind your approver that there are expenses waiting to be approved. You can send an email reminder.
To send an email reminder to the Approver.
l. Click Expense > ALL > Action > Send Email Reminder.
II. A confirmation message will show up at the top of the screen, once the email is sent.
Here is the sample email sent to the approver.
To know who is the approver of your expense/s. See the below article.