Composer require phpoffice/phpspreadsheet doesn't work
So I should install
sudo apt install php-xml
sudo apt install php7.0-gd
sudo apt install php7.0-mbstring
sudo apt install php-zip
also while running composer install/update or install new package adds
--ignore-platform-reqs
at the end of command, while add/install successfully for different environments.
I had the same problem, i fix it by doing this
composer install --ignore-platform-reqs