Invoice Numbers

My invoice numbers (for new invoices) used to be consecutive but now it’s showing numbers like 2109b and 2109d??
How can I make it just use the next consecutive number please?
Thanks

Hi @blade4life1889

Have you created one with a letter on the end recently? The system takes the last issued invoice number and adds 1 number/character to the end. If you correct the last issued one then it should correct itself in the next one.

Hope that helps!