How to configure invoice number?

Configuring “Invoice Number” is one of the premium features of Challan Plugin. In order to configure Invoice Number follow the steps below:

1. Go to the Settings of your Challan Invoice from your WordPress Dashboard.
2. Click on the Invoice tab.
3. Go to the Invoice Number section. There are 3 options in the Numbering Type drop-down. You can either choose a static number as 
   1. Prefix + Custom Sequence + Suffix
   2. Prefix + Order Number + Suffix  
   3. Order Number.
4. For Prefix and Suffix field you can add either static text or date macros. Available date macros are {{day}}, {{month}}, {{year}}
5. You can set the Next Invoice No. to start your invoice numbering from a custom sequence like 1212 or 10000 or 1 etc.