Hi,
I have no idea, how we did this much big and silly mistake. And thanks for letting us know this issue .
Here is the patch: open this PHP file:
yourdomain.com/modules/mod_virtuemart_flexible_dropdown_cart/mod_virtuemart_flexible_dropdown_cart.php
When you open the PHP file, look at the very top, you will instantly notice the text: "emt"
Delete these 3 letters. And everything is going to be okay.
Cheers.
Flexible Support Team.