Why do my exchange contacts show up in the messaging app when contacts sync is off?

[AC Question]

I have a Moto G 3rd gen with Android 6.0. I set up an exchange email account that has email and calendar synced, but not the contacts. When I go to send a text message, as I start to type in the recipient name, it shows the contacts on my phone followed by the contacts in my exchange global address list. How do I stop this? I only want to see the contacts on my phone.