Hi Boris2Hills,
In addition to comment, alemabrahao,
At the moment this is not an available feature (native report for Sponsored Guest login attempts on the dashboard). We take our customer feedback seriously and would encourage you to submit a feature request.
You can make a feature request by going to the bottom right-hand corner of any dashboard window and send the request through the "Give A Feedback" button.
Any wish that is made, sends an email to our Product Managers and Development Teams. These wishes are taken into consideration and are used to help shape our product roadmaps. The most wished-for items are incorporated into product development.
https://documentation.meraki.com/General_Administration/Other_Topics/Give_your_feedback_(previously_...
Also, you could use these options:
Option 1 - via API - https://developer.cisco.com/meraki/api-v1/get-network-splash-login-attempts/
In addition to other APIs to build it.
Option 2 - Network-Wide > Clients, on their client details page:
https://documentation.meraki.com/MR/Encryption_and_Authentication/Sponsored_Guest

Option 3 - You can setup a email forwarding rule for sponsor emails to get emailed to an address where you can then pull the logs/make a report from.
Option 4 - Cisco Marketplace the Backloop - sponsored guest access app - https://marketplace.cisco.com/en-US/apps/412605/backloop---sponsored-guest-access/features
This topic has been discussed here
https://community.meraki.com/t5/Wireless/Sponsored-Guest-New-Feature-Requested/td-p/176163
Additional documentation -
https://documentation.meraki.com/General_Administration/Cross-Platform_Content/Splash_Page#Splash_Pa...
If you have any questions, please don't hesitate to contact us.
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