@aleman77
It could be happening cause your first set of files has just singular numbers and computer is logical.
If your files are correctly named as 001, 002, 010, 011 , 012, 100, 112 (If you have till 999 files or
0001,0002, 0012, 0100, 0112 (if you have til 9999 files, it will not happening...