Hi Miguel,
Pls check the settings in below path:
Spro - Cross-Application Components - Master Data Synchronization - Customer/Vendor Integration - Business Partner Settings - Settings for Vendor Integration ( select as required vendor / customer) - Define BP Role for Direction Vendor to BP -
here you need to give the Cust/Vendor group and required Business partner role for that Group so that system will creates that BP from vendor / customer for the selected role only.
Then check the below setting also.
Spro - Cross-Application Components - Master Data Synchronization - Customer/Vendor Integration - Business Partner Settings - Settings for Vendor Integration - Field Assignment for Vendor Integration - Assign Keys - Define Number Assignment for Direction BP to Vendor -
here you have to give business partner group and vendor / Customer account group and activate the same number field as shown below image 2.
This may resolves your issue.
Thanks,
Rao

