Hi @Tzi,
For your first question, the device count seen in Organization > License info will not increase just from claiming a device to your inventory. The device must be added to a network before the device count increments. Are you still not seeing the device count go up after the switch is added to a network?
Regarding the dashboard connectivity issue, I would recommend following the steps listed in the Stacking Catalyst section of this KB. Note the following:
"It is expected that not all member switches will appear online until the stack is fully configured in the dashboard, as instructed in step 6.
Based on the number of members in a stack, the switch stack may require approximately one hour to become operational and connect to the Meraki Dashboard."
If you configure the stack in the dashboard after physically stacking the switches and the stack still does not come online after an hour, you may want to open a ticket with Meraki Support for further troubleshooting.
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