Uninstall Payment Surcharge (M2)

From a command line in the Magento root folder run: 

bin/magento module:disable Fooman_Totals Fooman_Surcharge Fooman_SurchargePayment
bin/magento module:uninstall Fooman_Totals Fooman_Surcharge Fooman_SurchargePayment --remove-data
bin/magento setup:upgrade
composer remove --update-with-dependencies fooman/surcharge-payment-m2

If you have used the Manual Installation Method (Option 2), then please delete the following files if they exist.

rm vendor/fooman/packages/Fooman_Totals-*.zip
rm vendor/fooman/packages/Fooman_Surcharge-*.zip
rm vendor/fooman/packages/Fooman_SurchargePayment-*.zip