Contact limit reached - trying to figure out how

Question

Basically we are over limit and I did some investigating but I am still baffled as to how.

I checked contact builder - email and mobile and we have a total of 1.7 million contacts.

Our limit is 1.5 million, but apparently we are over by 400,000 (1.54M)?

MC counts Contact Keys as individual records and they are unique, so by that logic there should be no duplicates correct?

My question is, is there a way for me to figure out if there are any duplicates and to gain a much more specific answer as to how our total is calculated. I see 1.7 contacts total in Contact Builder - All contacts, but apparently we are at 1.54m total contacts.

If someone uploads a list of contacts as a DATA EXTENSION using say an email, would that be counted towards our limit?

Answer 1

Mobile Push contacts get orphaned when you set a Contact Key via the SDK. The initial device registration occurs when the SDK is initialized. If it registers without a contact key then the servers assign a random GUID to uniquely identify the device/contact. When the SDK later sets a contact key the device is migrated from the original (anonymous) contact to the newly created contact. This can leave contacts in your org without a channel assigned.

These can be safe to delete. You should work with your account representative to identify and clean up these contacts.

Additionally, if you do not intend on sending push notifications to unknown contacts, you can delay the device/contact registration until a contact key is set. See https://developer.salesforce.com/docs/atlas.en-us.mc-sdks.meta/mc-sdks/mobile-push-sdk.htm for details on delaying registration.