LOV button for Supplier/Deliver to Location

In Responsive Self Service Procurement there is multiple LOV field e.g. UoM, Category, Supplier, Deliver to Location….

When we click LOV button in UoM or Category button it brings up result in LOV button. But where in Supplier and Deliver to Location field that button seems not working.

When we enter 3 characters it brings up results but if user click that button before entering or after entering 3 charchaters then its not working.

E.g. User enter 3 characters in the field and in hurry user clicked on LOV button as well. So result will be null but in actual, but possible values is there in system.