When using the Switch PHP Version option in your hosting control panel this will add a line to the .htaccess file in the root of your hosting. If there are conflicting versions in other .htaccess files within your hosting they will take effect from the location they are uploaded to and this is likely to the case here.
Check your hosting for .htaccess files that set the version of PHP to be used that conflict with the version chosen and remove those lines and this will resolve your issue here.
The command that sets the version of PHP to be used will be in the following format:
