accidentally changed the master link to my WP site

Hi, I just did a boo-boo and should have known better.

in the dashboard settings I changed the master url link from https://visualmechanics.co/blog

to:
https://visualmechanics/blog/about-us and it instantly locked everything into a internal 500 error…..

site no worky, help. please let me know where to revert that lethal mistake.

thanks, Robert

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