We have analyzed the reported query with our Filter source. in our source code we have maintain the dictionary collection for the filtered record. We have implemented this for the better performance in our filter.
Due to this the old records are maintain in excel filter dropdown, Based in this architecture, the Table.FilteredRecords gives the unique records to show in Filters. If you have used large dataset in application. The performance of the ExcelFilter may be decreased. So we have implemented the new method to clear all filter if you have reset the datasource.
Please reset the DataSource and clear the filer of the GGC using the above code. Please let me know if you need more information regarding this.