It says right in the documentation you linked to, under usage notes:
The following audit_trail_type values for valid for this procedure:
So... use those, not AUDIT_TRAIL_ALL. If you're managing different audit trail types, then you need to set the last archive timestamp individually for each type.
apparently you can't do DBMS_AUDIT_MGMT.AUDIT_TRAIL_ALL and purge all audits. Even if you try the actual value for the constant (15) it doesn't work.
Try SYS.DBMS_AUDIT_MGMT.AUDIT_TRAIL_AUD_STD for the aud$ and any others you need separately.
Only the AUDIT_TRAIL_AUD_STD, AUDIT_TRAIL_FGA_STD, AUDIT_TRAIL_OS, and AUDIT_TRAIL_XML audit trail types are valid.