Y axis motor not parallel to its support

[ak42]

Hello,
I bought an Acrylic Geeetech Pursa i3 pro B and it seems the Y axis
motor is not parallel to the acrylic support.
This makes the belt move laterally and lead to some friction between
the belt and the side of the pulley. And this will potentially cause
obstruction of the belt later.
Please take a look at the attached picture.
Could you please advise on how to fix this ?
FYI, this also happens without the belt.

Cheers,
AK42

[_kaktus_]

You probably forgot to add an attachment.