Increase the WordPress default upload file size limit ⬆️

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To check the current WordPress file upload limit, navigate to WordPress dashboard, click Media -> Add, and the upload limit will be displayed on the bottom.

php_value upload_max_filesize 64M
php_value post_max_size 64M
php_value max_execution_time 300
php_value max_input_time 300

And the second method, edit your theme’s functions.php file and add the following

@ ini_set ( 'upload_max_size' , '64M' ) ;  
@ ini_set ( 'post_max_size' , '64M' ) ; 
@ ini_set ( 'max_execution_time' , '300' ) ;