Revision Macro not working 4.4.1.23

I wanted to schedule a full back up of specific folders each day. After 5 days, I wanted the first backup to be overwritten. I used the macro function as follows:

Study_files|REVISION_NO_MAX05|.cbu

The first time it ran it created a file called: Study_files_REV_NO_0000000001.cbu

The second time it ran it created a file with exactly the same name, overwriting the first. I was expecting an “0000000002” file to be created and so on until “0000000005” after which time only then did I expect the “0000000001” file to be overwritten. Am I doing something wrong? Thanks