Placement of components in a "Confirmation with a textarea" pop-up dialog box

I really have an aim to get better at UX-design. As a part of a new feature I have come up with the following dialog box which prompts the user if he/she is sure that they want to delete followed by a compulsory textarea where the user is supposed to enter a comment to why he/she decided to delete the entity.

I'm not entirely happy with the outcome. The space on the right bothers me, but reducing the box in its width makes it look weird.

The first line says : "Are you sure you want to delete the form?". The second line says "Please provide a reason:"

Changing the colour scheme or the placement of the buttons is not an option (has to match the rest).

Would appreciate your opinion on how I can make it look better.