1. From Financial, go to "Actor library" -> "Customers".
2. Select customers using the checkboxes. Optionally use the [Select all] button.

3. Click the blue hamburger menu in the top right.

4. Click "Automatic open item settlement".
5. The selected customers are now settled.
Want to know more?
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Open items (invoice)
This article explains how to quickly create a printout of open invoices in Sapera