If you encounter issues with the PHP version readiness check, read this article. Below, we shed light on what conditions are problematic. Besides, we describe how to avoid them, fixing the issues. You can find more useful tips here: Magento 2 Cookbook.
Unsupported PHP version
The PHP version readiness check may fail since you’re using a PHP version that Magento doesn’t support. Check the supported PHP versions in System Requirements.
PHP version is not displayed
If the PHP readiness check in Magento 2 doesn’t display the PHP version (“Your PHP version is.”), you have to set up cron properly. You can learn how to do that here: Set up cron jobs.
Incorrect PHP version
A mismatch of PHP versions between the PHP CLI and the web server plug-in causes the check to report an incorrect PHP version. Usually, it happens when you install multiple PHP versions. However, it prevents the readiness check not always.
To fix the issue, you need to use the same PHP version for both the CLI and the web server. The former runs cron, the latter is responsible for the Magento Admin, Component Manager, and System Upgrade. Try the following resolution:
First of all, it is necessary to restart your web server.
Next, check the $PATH environment variable for several paths to PHP.
With the help of the which php command, locate the first PHP executable in your path.
Remove it if it is not correct. Alternatively, you can create a symlink to the correct PHP version.