There are multiple configurations which could cause that 10 minute you are experiencing. You’ll need to do a bit of digging the identify where, but I can certainly give you some pointers. Check the alert’s Activity Log tab to find the reason.
Two most popular mistakes/misunderstandings:
1.) Team settings - most importantly escalations. Inside OpsGenie, teams are a combination of routing features. An alert will notify the users in an order, according to the escalation policy in your target team. Just to give you an example: if your escalation policy is pointing to you at the 10 minute mark, your notifications will be coming at that time as well.
Make sure you check your Routing Rules - Escalation Policy timings and your schedule.
2.) Notification Rules. Each User has a set of rules under their profiles. The “New Alert” notification rule is the one which is executed when the team logic is pointing to a user. If that does not have an immediate notification step, that would explain the delay as well.
Additionally, there are some advanced options to delay notifications for alerts - but I’m positive it should be one of the above.
If you share an alert through our support chat, we can take a look as well!