Hello
Hope you are doing well.
Sorry for the inconvenience you are facing.
You will be glad to know that We have fixed the EA Login| Register Form- Security token did not match error in our latest update of Essential Addons
So Please update the latest version of Essential Addons for Elementor v.5.4.2.
After the update, if you are still facing the issue that means It might be a caching issue. So can you please try doing this following: To regenerate assets, you can go to wp-admin -> Essential Addons then, switch to the ‘Tools’ tab and hit the ‘Regenerate Assets’ button. Check out this screenshot: https://d.pr/8467Wx
If the issue still persists then, It is possible that your browser cache is not updating properly.
Please kindly clear the cache of your browser and hard refresh your browser with (cmd/Ctrl) +Shift + R.
If you are using a caching plugin, you need to purge the cache from your plugin option and then deactivate the caching plugin temporally so that the new update could take effect.
Also, you could check this on a different browser.
Hopefully, it will fix the issue.
Let me know how it goes.
Thanks