“Upload_max_filesize”, is a hosting issue, not the theme issue, which can be easily fixed. I would kindly request you to contact your Hosting Service Provider about the issue. They will surely fix the issue.
You can refer to below links as well for the fix.
- http://www.wpbeginner.com/wp-tutorials/how-to-increase-the-maximum-file-upload-size-in-wordpress/
- https://wordpress.org/support/topic/tthe-uploaded-file-exceeds-the-upload_max_filesize-directive-in-phpini/
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