Login to Self Hosted WordPress without URL

Hello. I had to give my URL to a company because they say it was trademark violation. So I gave it up before I could export the files. Now I’m stuck with just the wordpress install and the files. How do I login to my site so I could export all the post to the my new URL.

ADDITIONAL INFO:
-my OLD URL was addon domain
– i can access the frontpage of the site right now by goin
https://www.myORIGINALDOMAIN.com/MY-ADD-ON-DOMAIN-THAT-I-GAVE-UP/index.php
– when i type ‘wp-admin’ where the ‘index.php’ is I get error.

Is there a way I could manually download all the post, comments without loging in?

Thanks in advance for your help.

janet