Resolution

OnPrem clients with Tyler Deploy access and Deploy/Configure permissions:

In Tyler Deploy, navigate to Product Configurations > Tyler Cashiering Server
Expand Tyler Cashiering Server section
Check off Show advanced
Scroll down to IIS Info
In the Whitelisted Trusted Domain(s) field, add the site referenced in the error
1. Ex: frame-ancestors https://*.tylertech.com
Scroll up and click Save
Click Go to Deployment
Run Cashiering deployment with Force Redeployment checked off

SaaS clients:

Please contact Tyler Systems Management Support or log a case via the Online Support Client Portal

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