By default, phpmyadmin has a max upload size of 50 MiB. To increase this value on a cPanel server please do the following:
- Login to WHM as root
- Go to Server Configuration » Tweak Settings
- Click on PHP tab
- Update the values `max upload size` and `max POST size` with the max file size you need.
- Don't forget to update `max execution time` to a proper value (in seconds) to avoid getting the upload process fail if it takes a longer time than the value set in `max execution time` already.