Unable to upload file

The upload file button is not accepting the correct format file of excel. It keeps on saying that it does not have the right extension even if the document does

I have cleared your form's cache. Can you please try again and let us know if the problem persists?

Thanks.

Still not accepting xls format
Sent from my iPhone 7 plus
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Thanks for the update, pnaaf.

I have made changes on the form field and it appears to be fixed now. Please test it this time and let us know if the problem persists.

Thanks.

After receiving this response from you. Tested and the same response
Sent from my iPhone 7
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I tested your form and I can see the error, that actually happens since the extensions have been entered incorrectly, please see how there is a space at the beginning of the first extension and there is a comma at the end of the last one: 

The extensions must be like this: 

This worked on my end, please also check this guide about adding file types:  https://www.jotform.com/help/29-How-to-Change-the-Allowed-File-Types-in-the-Upload-Field

I hope this helps.