Thanks for your reply.

You mention the following:

This is because even the Custom transaction numbers is turned off, the system will constantly create an entry number.

Even in a private browser (Chrome Incognito Mode) and when viewing invoices from the Sales page, there do not appear to be any invoice numbers associated with the invoices created today and therefore the system does not appear to have created an entry number.

Further, when I check A/R from the Chart of Accounts, the fields where invoice numbers usually display are blank, further confirming my suspicion.

I reiterate that I changed no settings, yet after the new invoice UI rolled out, subsequent invoices no longer contained numbers. This seems like a bug on your end. I'd appreciate more information on how to troubleshoot this.