Multi files upload doesn't work with iPad & iPhone, got 400 bad request

Hello everybody,
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I have a Joomla website. That is using Chronoforms5 to allow the user to upload a file to the server. I am using Bluehost server to store the website.
You can refer to URL: https://new.ipshk.org/index.php?option=com_chronoforms5&chronoform=demo-fields-multiplier
That form is working fine on desktop and Android devices. But when I choose and submit multiple files from Browse of an Apple device (iPhone, iPad), I get a 400 bad request.
I checked the log of the website on the server. But I see no error log. So i'm not sure issue related Server or Chronoforms.
Anyone could help me know what is the cause of the issue?
Thank you.

Hi hahieuit,
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I think that Apple still gives all the uploaded files the same name ;-(
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Please see this FAQ It was written for CFv4 , but something very similar should work for CFv5.
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Bob

Hi Mr Bob.
I'm very happy when i received your reply.
I've read and tried that post ago. But i still got error.
As that post, we just change name when files is same type.
I tried attached 3 files different type, a pdf file, a docx file and a gif file.
But i still get 400 bad request😟
Are you know cause of issue? Hope get more support from you.
Thank you.
Ha