Disable and flush Magneto Cache from admin area. Go to System → Cache Management.
Make sure that you have compilation disabled before installing extension. System → Tools → Compilation page and click on Disable button. After Installation you can reenable compilation.
Extract Hips.M1.v1.0.zip. Upload the app folder to your Magento root directory using a FTP client.
Extract Hips.M2.v1.0.zip. Upload the app folder to your Magento root directory using a FTP client.
Log into the admin panel and navigate to the Cache Management page (System → Cache Management), selecting all caches, clicking "disable" from the drop- down menu, and submitting the change. Or by running the command "php bin/magento cache:disable" from your magento root directory in command line.
Navigate to your Magento 2 root directory using "cd" in command line. Enter the following at the command line
php bin/magento setup:upgrade
php bin/magento setup:di:compile
php bin/magento setup:static-content:deploy
Enable Magento Cache through System → Cache Management or run command php bin/magento cache:enable from your magento root directory.
Go to Stores → Configuration, and to Sales → Payment Method.