If you visit the below URL - are you attached to that AP? http://my.meraki.com/   Check out "Wireless Health": https://documentation.meraki.com/Platform_Management/Dashboard_Administration/Operate_and_Maintain/Monitoring_and_Reporting/Meraki_Health_Overview   Also, click the client in the dashboard and review the roaming events.  Is the client making any bad decisions? ... View more

I would start by looking at the "Wireless -> Health" and "Assurance" tabs in the dashboard Start high level and dig down into any problems you see there.   As @alemabrahao suggested above, opening a support case may also be the better option if you don't have much experience in the dashboard. ... View more

Note: The device will still receive an IP address and will be able to resolve DNS names. Note: The EAP exchange will still be allowed for wireless clients, and devices will be able to associate with an SSID. The block will apply to client traffic after the 4-way handshake is completed. Blocking or Allow listing a Client  There are two ways to allow list or block a client on the Cisco Meraki dashboard. Note: There is a limit of 3000 clients for allow listing and 3000 clients for blocking. An error will appear when attempting to allow list or block more than 3000 clients.     Take a look at this document and consider using iPSK without Radius.   https://documentation.meraki.com/MR/Design_and_Configure/Configuration_Guides/Encryption_and_Authentication/IPSK_Authentication_without_RADIUS ... View more