No Business Partner in BP when creating customer

Hello all: we have a problema when creating customers with method MAINTAIN _BAPI in CMD_EI_API.

Using tcode XD02, when creating a customer with acc.group ARRE, a bussines partner is automatically created and can be displayed using tcode BP

When creating a customer id with method MAINTAIN_BAPI in class CMD_EI_API, the business partner in BP is not created.

Any clue about how to get it?

Thanks in advance

regards

Valentín