Please try these commands:
admin system-options -delete CORS_ALLOW_SUBDOMAINS
admin system-options -add CORS_ALLOW_SUBDOMAINS true
then you can use the previous commands to just add the root domain
Add root domain:
admin system-options -add CORS_ALLOW_ORIGIN yourserver.com -multi
Add root domain URL:
admin system-options -add CORS_ALLOW_ORIGIN https:// yourserver.com -multi
Add site URL:
admin system-options -add CORS_ALLOW_ORIGIN https://sharepoint. yourserver.com -multi
Please check if you are seeing this error when you open the web browser Developer Tools > "Console"
Refused to frame '< url here >' because an ancestor violates the following Content Security Policy directive: "frame-ancestors 'self'".
Many web apps have a "CSP / Content Security Policy" that block other sites from embedding their content in an iframe.
Here is what that may look like on the "Network" tab.
If that is the case, then we will need you ask your Sharepoint administrator what their "CSP" policy is.