Increase limit of maximum file upload size. If .htaccess file method doesn't work for you then you may edit php.ini file, hope second one must work 😊

.htaccess

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /staging/
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /staging/index.php [L]
</IfModule>
# END WordPress

# Increase Limit of Maximum upload file size
php_value upload_max_filesize 100M
php_value post_max_size 100M
php_value max_execution_time 300
php_value max_input_time 300

php.ini

; Maximum execution time of each script, in seconds
; http://php.net/max-execution-time
; Note: This directive is hardcoded to 0 for the CLI SAPI
max_execution_time=300

; Maximum amount of time each script may spend parsing request data. It's a good
; idea to limit this time on productions servers in order to eliminate unexpectedly
; long running scripts.
; Note: This directive is hardcoded to -1 for the CLI SAPI
; Default Value: -1 (Unlimited)
; Development Value: 60 (60 seconds)
; Production Value: 60 (60 seconds)
; http://php.net/max-input-time
max_input_time=600

; Maximum amount of memory a script may consume (128MB)
; http://php.net/memory-limit
memory_limit=256M

; Maximum size of POST data that PHP will accept.
; Its value may be 0 to disable the limit. It is ignored if POST data reading
; is disabled through enable_post_data_reading.
; http://php.net/post-max-size
post_max_size=8000M

; Maximum allowed size for uploaded files.
; http://php.net/upload-max-filesize
upload_max_filesize=2000M