Jumps in invoice lists

Hi,

We are having troubles with Zoho Books. When we try to get lists with all the month invoices the sistem makes "jumps" at the list making "dissapear" real invoices. Than make us have huge financial troubles every months.

In the image attached you can see how jumps from invoice 05108 yo 05110 when there is a real 05109 invoice in the sistem.

Regards