next available sequential number dependant on two additional variables

[Driver84]

Good day all,
I'm looking for some assistance in how to generate the next available sequential number dependant on two additional variables.

I am creating a document register and the two controlled variables are (the document owning) Group and Type.


The titles of the documents are to follow the format: GGGG_TTTT_NNNNN

Where:
GGGG, for example, is Group-A, Group-B, Group-C, etc.
TTTT is Type-A, Type-B, Type-C, etc.
and NNNNN is a numerical identifier using sequential integers of the format 00000, 00001, 00002, etc.

Group-A can have documents of Type-A, and Type-B both with the numerical identifier 00000, for example:

Group-A_Type-A_00000
Group-A_Type-B_00000


How can I ensure that if Group-A produce another Type-A document that the next available numerical identifier of 00001 is used, and allow another Type-B document to be produced that would also use 00001 as its next available numerical identifier?

MS Excel v2209 for Office 365.