Why do some number sequences return "000000" instead of a new number?

Since about a week, the number sequences for sales invoice numbers and vouchers return "000000" instead of the next number of the number sequence in one system.

So far I tried the following:

• check manual, continous and other settings of the number sequence: all seems to be in order
• recreate the number sequences using the wizard: the newly created number sequence still does not work
• check other number sequences: they work
• check number sequences in other legal entities and other systems: there the number sequences work

I also found Issue with number sequence after upgrade to AX2012 R2 in place (although the system with the problem was not upgraded), which brought me to the getNumInternal stored procedure. I compared the procedure with another system, but found no differences. I do not think it is a permission problem since the problem only occurs for some number sequences in one legal entity. My next step will be debugging it, but maybe someone has another idea?

The goal is that the number sequences for sales invoice numbers and vouchers again work as normal.

The system is version AX 2012 R2 CU7.

It was a permission problem after all. I was thrown off because the stored procedure is only called for continuous number sequences and the system in question has those only in the legal entity where the problem occurred. After adding the AOS service user to the permissions of the stored procedure, the correct number was returned.