I can only speak from my own experience, not on behalf of Joomshaper, but this is almost certainly a web hosting 'issue', rather than an issue with SP PageBuilder.
Many web hosts have max upload limits declared in the php.ini file for the version of PHP that you are using, sometimes even as low as 8MB (I have even seen 4MB!). If you have CPanel with tools for changing PHP versions, you might have tools to edit the max upload sizes in your PHP version, probably called MultiPHP INI Editor (although you should Google how to change these values first, as there is a difference between post_max_size and upload_max_filesize).
If these tools are not available to you in your web hosting control panel, or you are not confident using them, you will be able to send your web host a support ticket to request an increase in max upload size etc.