AP Invoice Workbench - How to personalize supplier number when Supplier=Invoice Creator/user logging

Hi support,

AP Invoice Workbench - How to personalize supplier number when Supplier name = Invoice Creator/user logging user name invoice should not be created since user and employee names are identical. how do restrict if the employee name/user logging name same as the Supplier name?

I tried with page personalization below statement but it did not work.

#{bindings.VendorNameTemp.inputValue} != {securityContext.userName}

Could you please help me is there any option to restrict this?

Thanks