Hello Ci,
This was a functionality that the number of items being beyond a certain threshold all the processing will happening in background process. Only way to avoid could be to run in foreground. This customizing is done as shown below
SPRO--->SAP Supplier Relationship Management--->SRM Server--->Cross-Application Basic Settings--->Background Processing--->Define Threshold Value for Background Processing
Check what is threshold you have maintained for your BO (BUS2200 in this case) and retest the issue.
Thanks and Regards,
Veera