I had the same issue ( also happened to me when I added external url in the odoo Website, the redirections didn't work well )

Modify the Odoo Configuration File: 
Ensure that your Odoo configuration allows cross-origin requests. 
Open your Odoo configuration file (usually located at /etc/odoo/odoo.conf).

Add or update the proxy_mode parameter to True:

proxy_mode = True

 then restart odoo : 

sudo systemctl restart odoo

and it should be working, if not then add the proxy_header configuration and allow_cors headers in your nginx , restart nginx and it should be working.

Hi,

This seems something related to your deployment, so please be sure you are following the proper installation instructions.

[Reason:-You can't access a <iframe> with a different origin using JavaScript, it would be a huge security flaw if you could do it. For the same-origin policy browsers block scripts trying to access a frame with a different origin.]

please refer:-

https://stackoverflow.com/questions/25098021/securityerror-blocked-a-frame-with-origin-from-accessing-a-cross-origin-frame

https://github.com/odoo/odoo/issues/26672

Regards