And you can do so via TeamMail, SFI Chat (leave a message even if he (she) is not online) or email them at his (her) personal email address.
All of his (her) contact information is provided at https://www.sfimg.com/Resources/Leadership?id=xxxxxxxx (your sponsor's SFI ID where the x's are.)
However, I would suggest that before you seek your sponsor's attention, enter the keywords of your particular issue that you need guidance on in the search box at the top of your page and see what comes up.
Chances are that there's something in the Forum or in 'Ask SC' that will help you and could also inform any discussion that you may have later on with your Sponsor.