Hi Akhilesh,
As you have populated the data using the value node, the current data retrieved also will be a value node and not a entity. Please change the type of entity to CL_BSP_WD_VALUE_NODE and try.
lv_entity_c TYPE REF TO cl_crm_bol_entity CL_BSP_WD_VALUE_NODE
Regards,
Thanabalu S.