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Description:
File Type is not allowed error message thrown when AutoUpload is set as false while selecting the file individually.
Sample: https://blazorplayground.syncfusion.com/VjLJZKXFVbqCJppp
Customer’s sample: https://blazorplayground.syncfusion.com/BtVJjqXvhbdmAOdl

Validation Details:
This issue doesn’t occur for AutoUpload true, with Async setting and uploading multiple files at a time.
Note: This issue is occurring with the combination of AutoUpload false and selecting file individually.
Replication Procedure:
Expected: File should upload properly.
Actual: File type is not allowed error message thrown for first file.