In order to be able to hire your freelancer you will need to add your address. To do this, go to Settings > My Info > Company Contact and add your full address. Thank you.
Hey, I got the same error and resolved it by going to Settings -> My Info -> Address and removing the special character (in my case a ß) and going back to the poposal afterwards.
I hope this helps!
I had the same issue.
It was fixed when I filled out my address details. I guess empty address fields cause that problem as well and not just special characters. Cheers.