Thank you for reaching out @Tiara_Moske and apologies for the inconvenience here.
As it stands, if you have enabled your email notifications for Activity updates, you should receive an email notifying when somebody has @mentioned you in Asana. Please note that if you’re receiving multiple notifications, Asana will automatically batch them into a single email to avoid spamming your mail box.
Can you please confirm you have these notifications enabled?
If this is not the issue, I would recommend your colleague’s to contact our Support Team so they can take a closer look into your their account and assist them further.
I hope this helps Tiara! Looking forward to your reply!