gme_api_pub.create_material_txn - error has occured during the reservation

Hi,

I have create custom WIP Issue API Procedure in OPM.

While trying to execute Standard API gme_api_pub.create_material_txn in custom API with necessary parameters, but it return with error as

An error has occured during the reservation. User-Defined Exception in Package GME_COMMON_PVT Procedure GET_MATERIAL_DETAIL

Kindly help to resolve on this

I just add the calling program......

Declare
ln_user_id                NUMBER;
   l_lot_rec                 apps.gme_common_pvt.mtl_trans_lots_inter_tbl;
   ln_message_count          NUMBER;
   lvc2_message_list         VARCHAR2 (2000);
   lvc2_return_status        VARCHAR2 (2000);
   l_mmti_rec                apps.mtl_transactions_interface%ROWTYPE;