DEP is very handy if its been setup. As mentioned your only option is to factory erase the devices. Before you do this save yourself time by
1. Making sure devices are enrolled in DEP
2. Make sure Meraki is linked to your DEP account
3. Make sure your Apple VPP account is linked to Meraki
Once those are all setup and you have tagged the devices with the appropriate tags everything should be vey easy and quick.
@Deborah Are you new to Meraki?
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