If you'd like to dismiss a reminder, you can click the X next to it. This will cause it to disappear from your dashboard.
If you dismiss a balance reminder for a client, it will not appear again until that client's balance changes.
This means that if you accidentally dismiss a client's balance reminder, you can make it appear again by following these steps:
1) Record a test payment toward the client's balance. (Any amount.)
2) Wait 24 hours.
3) The client's balance reminder will appear in your reminders section.
4) Delete the test payment.