Can’t log in to specific websites

Unable to access certain websites (3) through their login page. All other websites load correctly.

Highmark.com members log in – After entering the MFA code, spins and never loads

pplelectric.com – after entering username and PW, returns to the blank log-in screen

Alizhotel.com – log in screen immediately times out

Running Windows 11 Home ver. 10.0.26200 Build 26200

1. Tried Chrome (ver. 151.0.7922.140) . Edge & Firefox

2. Cleared browser cache

3. Flushed DNS

4. Tried with firewalls (MS Defender) turned off

5. Tried changing passwords

6. Tried incognito window

7. No extensions are installed

8. Each website CAN be accessed when I use an older PC in my home (using Chrome)

Any suggestions would be greatly appreciated. Thank you in advance.