Rule 46 (b) of the CGST Rules 2017 specifies that the tax invoice issued by a registered person should have a consecutive serial number , not exceeding sixteen characters, in one or multiple series, containing alphabets or numerals or special characters – hyphen or dash and slash symbolized as “-” and “/” respectively
This validation will come into effect in ERPNext from the new fiscal year i.e FY 2021-22. If you encounter an error similar to one shown in the screenshot below, follow the below steps to resolve the issue and add a new naming series for Sales and Purchase Invoices
Step 1: Go to "Naming Series" doctype and select transaction as "Sales Invoice"
Step 2: Add a new naming series having maximum upto 16 characters. For eg INV-.YYYY.-.#####. Add this as the first option and don't check "User must always select" inorder to make this as the defaut naming series
