I know it's annoying, but have you tried to add an address from an official postal service website for your region?
If you're in the USA, use
www.usps.com and for example, (this works if your Account is an NA region, it doesn't matter if you aren't) search for Google's headquarters in the USA, then put the address shown (check it on google search first, then match it on usps.com) exactly into the MogStation form.
This is known to work for many people, can use other company address as well such as Microsoft.
Might help you for the time being until they fix the address issues, worth a try.