my.meraki.com is a locally-hosted site useful for configuring an AP when it cannot reach the Meraki Cloud. This is often seen on a static, non-DHCP network or when there are strict firewall rules. To utilize my.meraki.com use the guide here: https://documentation.meraki.com/zGeneral_Administration/Tools_and_Troubleshooting/Using_the_Cisco_Meraki_Device_Local_Status_Page .
If after following that guide you still cannot connect to my.meraki.com, take these troubleshooting steps:
1.) Verify that your Client Device drivers are up to date.
2.) If a client device uses a statically assigned network configuration, set it to DHCP.
This is because a Meraki MR Access Point that cannot reach the cloud will instead broadcast a default SSID of "Meraki-Scanning." The AP takes an address of 10.128.128.128 and the SSID runs DHCP and will try to assign any clients that associate with it an address (see figure 1). This is merely to provide connection between a client and the AP for local configuration.
If a Laptop is statically configured it will not be able to associate with the AP and it will be unable to reach my.meraki.com url and the client will not be able to configure the AP locally.