Problem with calculated amount in VM

Hello !

I created a coupon code giving -5% on all products.
But the total amount of the order is false.

For example:
Subtotal: 23,99€
Coupon: -1,20€ (correct)
Total VAT included: 21,34€ (why ?)

Thanks in advance.
You can test with coupon code IBM5 on www.sajoushop.be

Version: 1.0.9

could be alot of reasons. Are you using discount before tax? If so, this may be of help:
https://awodev.com/blog/virtuemart-coupon-error-discount-before-tax

Thanks !
It works fine now !