If you submit the claim showing 29 units for visits from 11/2-11/30 and the insurance company splits them out to 29 separate lines, that's not recoding, that splitting the units out to individual lines. Actually, most carriers would require that you bill them that way. In any case, even if they split it out to the 29 lines, they should process the same as if it was grouped together. If you don't agree with the payment then you should call to inquire as to the way they processed it.
Michele