Can not able to upload image more than 2 mb

I am unable to upload file more than 2mb. My max upload file size at server end is 50 MB. To double check I tried with uploading via Media library and its working fine so no issue with server side.

I have also tried with following but it also don’t work.
wp-content/plugins/contact-form-7/modules/file.php
and changes 1048576 to 10048576

$allowed_size = 10048576;

I have added : [file* file-968 limit:20mb]

Can you please help ASAP ?

Thanks

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