Firmed planned orders

Hi Experts,

We are having a material with MRP type 'M0' and Planning time fence maintained as '0'.

But this is generating high number of duplicate planned orders (please refer to the attached screenshots).

Now I have two queries:

1. Why these high number of firmed planned orders are created inspite of maintaining the planning time fence as '0' day.

2. How to delete these planned orders. Can it be achieved by a Z program using Bapi - BAPI_PLANNEDORDER_DELETE along with BAPI_TRANSACTION_COMMIT. Is there any alternate way for the deletion.

Looking for your feedback.

Thanks and regards,

Kaushik Basu