Yubikey & Codes not working at specific domain

This plugin worked like a dream until I migrated my site from a development site at a different domain to the current site. I have used the plugin for four months with no problems on several sites.

Neither the Yubikey nor the back-up codes work at the current site. When prompted to touch the Yubikey (it is always inserted in my desktop), there is no response and I have to rename the plugin in cPanel’s File Manager to access the WordPress dashboard.

I have deactivated and tested other plugins for conflicts at the development site. There was no problem accessing the site during the test at the development site. I then migrated the files to the current domain and no access.

Are there known conflicts with themes? I’m using the Astra theme with a home page created with Elementor page builder.

There are not many options for integrating Yubikey with WordPress. I found this plugin after experiencing problems with other plugins that were abandoned or very dysfunctional.

I don’t want my login page unprotected. 2FA through Yubikey has worked for me for several years.

Any suggestions?

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