Maybe you are using some caching mechanism?
As far as I understood, you go to PageView3, select a file and upload it. When the file is uploaded you update your database. Then you go to PageView1 and search in the combobox (I guess it loads its items with load-on-demand). At this stage can you debug and check if the query contains the newly added records from the database? If the datasource contains the new records - they will be available in the combobox as well.
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