Can't login into admin panel

Can someone please help.

So I installed a wordpress installation locally and transferred in onto my server at robtlarkin.com/wordpress It was working and everything was fine. I was leaving it here while i was finishing some stuff on it. Then i had intended to transfer it to the domain https://www.boundariesarebeautiful.com, which my client had as a wordpress.com site.

But now i can’t login into the admin panel at all and the site appears to not have the theme applied to it anymore?? Not sure what happened

Anyone have any suggestions as to what might have happened or how i should go about fxing it. Also the original https://www.boundariesarebeautiful.com is not working now either.