For those users who may have added a custom GCM/FCM ID and Key, sometimes you may get a warning when sending a campaign stating some notifications were not deliverable due to a "Mismatch Sender ID".
This essentially means that those push subscribers are active but we were unable to reach them due to a technical set up issue.
This usually is a result of one of three reasons:
Reason #1: You did not add the correct GCM key in your Aimtell dashboard
A simple fix - double check that you've added the correct GCM/FCM ID and Key in your Aimtell dashboard.
Reason #2: You have a conflicting manifest file
When a website visitor subscribes to push notifications on your website they are automatically attached to your website's Sender ID (aka GCM or FCM ID). While this Sender ID is specified within your Aimtell dashboard, it can also be manually set with a "manifest" file on your website.
If you have a manifest file on your website with a different Sender ID than what is stated in your Aimtell dashboard, it will likely cause a Mismatch Sender error. To fix this, simply make sure these two IDs are the same.
Reason #3: You removed a valid, existing Sender ID/Key from Aimtell
Let's say you set your Sender ID to 461783654421 within the Aimtell dashboard and collected a few subscribers. Then, sometime later, you deleted that ID and added a new one - 238646170294.
When sending a push you may likely have this issue since those initial subscribers are all attached to 461783654421 but that ID and Key no longer exists in Aimtell. To fix this, simply add the original Sender ID and Key back into your account.
Note: You can have multiple Sender IDs and Keys under your account, and toggle which one is the primary (aka which all new subscribers should be attached to)
While the system will automatically attempt to update subscribers affected by the Mismatch Sender ID issue to the correct GCM ID and Key, sometimes this can take some time.
If you'd like to speed up the process, contact firstname.lastname@example.org and we will manually update your subscribers for you.