I am getting this error, even if the series and everything is correct

[indranibhagat]

[Lakshit_Jain]

Character limit as per GST is 16 digits including special characters.

Try using a smaller naming series.

[rishabgupta]

This is a GST compliance validation , A document numbers cannot exceed 16 characters (including alphabets, numerals, and special characters like - and /

This applies to any document where e-invoice/IRN is generated.

Fix: Shorten your naming series

[raghavr]

Can you share screenshot of the Document Naming Series configuration?

[indranibhagat]

Sure. Here is the screenshot.